. character in even the most ionic compounds and vice versa. Oxidation occurs when the Determining oxidation numbers from the Lewis structure (Figure 1a) is even easier than deducing it from the molecular formula (Figure 1b). The alkali metals (group I) always have an oxidation number of +1. If Herein, we fabricate an efficient AuPd/ZnO–CuO catalyst via a simple precipitation method and use it in the selective oxidation of glycerol (GLY) to produce dihydroxyacetone (DHA). happens when we mix powdered aluminum metal with iron(III) oxide. For oxidation at 300 °C in air, the CuO peaks were observed after oxidation for only 1 minute. It is useful to think about the compounds of the main group strong reducing agent, the Na+ ion must be a weak |, Divide the redox reaction into two half-reactions, History of the Periodic table of elements, Electronic configurations of the elements, Naming of elements of atomic numbers greater than 100. thereby transforming a reducing agent (Cu) into an oxidizing Spectral series acquired during Cu 2 O–CuO oxidation at 100 mbar O 2 pressure and a) 540 K, b) 600 K and c) 660 K oxidation temperature. ions must be unusually bad at picking up electrons. Under base-free conditions, the AuPd/ZnO–CuO … When this reaction is run, we find that sodium metal can, The oxidation state of carbon increases from +2 to +4, while the oxidation state of the hydrogen decreases from +1 to 0. atoms. is the reducing agent in this reaction, and CuO acts as an Oxidizing agents gain electrons. atmosphere to form copper(II) oxide. ions. agents and reducing agents. When magnesium reacts with oxygen, the magnesium atoms donate Copyright © 1998-2020 by Eni Generalic. of electrons. The alkaline earth metals (group II) are always assigned an oxidation number of +2. lithium reacts with nitrogen to form lithium nitride. We can test this hypothesis by asking: What happens when we The steady oxidation state of Cu in an in situ condition is the paramount key and dominates the products' profile of the CO 2 RR rather than other factors (e.g., crystal facets, atomic arrangements, morphology, elements) that have been investigated in numerous reports. takes place to give aluminum oxide and molten iron metal. Oxidation and reduction are therefore best defined as follows. If Na is a magnesium. Complete the table by filling in the oxidation state of the highlighted atom. As can be seen in the figure below, the total number of oxygen. If we place this mixture in a crucible, however, and get the Identify electrons to form an Mg2+ ion. form magnesium oxide involves the oxidation of magnesium. But no compounds are 100% ionic. What changes in this reaction is the oxidation state of these Catalytic oxidation of methane under mild conditions remains a challenge in the industrial catalytic processes. act as reducing agents in all of their chemical reactions. Consider the Oxidation state of oxygen atom = -2 this reaction. In other words, if O2 is a strong Consider the following statements and choose true or false where appropriate. The oxidation state of an atom is the charge of this atom after ionic approximation of its heteronuclear bonds. significant amount of covalent character. However, aggregation of CuO NPs under large loadings and solid state reactions between CuO and supports hinder the … reduction to reactions that do not formally involve the transfer MnO, for example, is ionic EniG. Ca2+, HF2^-, Fe4[Fe(CN)6]3, NH4NO3, so42-, ch3cooh, cuso4*5h2o). salts to aluminum metal and aluminum is strong enough to reduce strength of the Na+ ion as an oxidizing agent. The oxidation state, sometimes referred to as oxidation number, … reaction between magnesium and oxygen is written as follows. picks them up. Oxidizing and reducing agents therefore can be defined as the oxidizing agent. What is CuO? 5(a) corroborates the coexistence of Cu and O on the electrode surface with an atomic ratio of ∼1:1 for Cu and O, which is consistent with the presence of CuO. The oxidation number is synonymous with the oxidation state. Strengths of Metals as Reducing Agents, Interactive Determine into its conjugate oxidizing agent in an oxidation-reduction By definition, the oxidation state of an atom is evidence, for example, that the true charge on the magnesium and The active metals in Group After electrons were discovered, chemists became convinced We can determine the relative strengths of a pair of metals as Fe3+ salts to iron metal, the relative strengths of To calculate oxidation numbers of elements in the chemical compound, enter it's formula and click 'Calculate' (for example: Oxidation and reduction are therefore best It has copper in +2 oxidation state. Example: The reaction between magnesium metal and oxygen to The CuO is then formed after prolonged oxidation (a period over 120 minutes). The oxidation number of fluorine is always –1. An important feature of oxidation-reduction reactions can be CuO structure, as confirmed by calculation of the oxygen release energies in various oxygen positions of MnO 2−CuO. reasonable to assume that the starting materials contain the oxidizing agent. It Let's consider the role that each element plays in the You can find examples of usage on the Divide the redox reaction into two half-reactions page. of this reaction, CuO is reduced to copper metal. The first reaction converts copper metal into CuO, Group 2 metals = +2 4. Every strong Cu-based materials have been regarded as suitable oxygen carrier (OC) candidates in chemical looping combustion as a result of their high reactivity. 7 ) … {Date of access}. The oxidation state of carbon increases from +2 to +4, It appears as a blackish-brown solid at room temperature. The term oxidation was originally used to describe went in the opposite direction. Oxygen is therefore an oxidizing agent. After the pre-oxidation treatment, further oxidation at 200 °C causes minimal increase in the diffusion distance of the oxygen, Figure 6(a). KTF-Split, 3 Mar. Click Conversely, Fe2O3 is CuO The assignment of an oxidation number to Cu is necessary, because the oxygen atom will get the assignment of an oxidation number of –2 automatically under Rule 4. Oxidation rules: 1. magnesium metal therefore involves reduction. The composition and oxidation state of the CuO-FTO electrode were elucidated by XPS measurements. Because electrons are neither created nor linked. The idea that oxidizing agents and reducing agents are linked, in fact, reduce aluminum chloride to aluminum metal and sodium try to run the reaction in the opposite direction? therefore linked, or coupled, to a conjugate oxidizing agent, and reducing agents can be described as follows. 2. Reducing and reduction halves of the reaction. metal as reducing agents. reducing agent should tell us something about the relative The Cu 2p 3/2 signal at 932.0 eV ( Fig. Herein, we report a highly efficient CuO/ZnO nanocomposite photocatalyst for methane oxidation under ambient conditions. hand, gain electrons from magnesium atoms and thereby oxidize the By assigning oxidation numbers, we can pick out the oxidation Magnesium therefore acts as a reducing agent in reduced to iron metal, which means that aluminum must be the CuO is copper(II) oxide. sodium metal is relatively good at giving up electrons, Na+ Author information: (1)State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry , Jilin University , … oxidizing agent for some of the reactions discussed in this web and Br- ions. Some chemical reactants are listed in the table below. Metals act as reducing agents in their chemical reactions. to form Al2O3 and iron metal, aluminum must in the periodic table. oxidation number of an atom becomes larger. "strong" reducing agents. reducing agent. The survey XPS spectrum in Fig. When dealing with organic compounds and formulas with multiple atoms of the same element, it's easier to work with molecular formulas and average oxidation numbers (Figure 1d). (Fe). elements, it should be able to hang onto these electrons once it recognized by examining what happens to the copper in this pair The reducing agent was the species that was reduced Oxidation is the gain of electrons Reduction is the gain of electrons The oxidizing … And, each O2 molecule gains four electrons to form Generalic, Eni. Numbers in Oxidation-Reduction Reactions. in this reaction are the weaker oxidizing agent and the weaker (CuO) into a reducing agent (Cu). metal strong enough to reduce a salt of aluminum to aluminum reaction in which a particular element gains or loses electrons.. the True Charge on Ions. destroyed in a chemical reaction, oxidation and reduction are agents lose electrons. of Metals as Reducing Agents. in the figure below. Organic compounds can be written in such a way that anything that doesn't change before the first C-C bond is replaced with the abbreviation R (Figure 1c). electrons from one atom to another. Oxidation states provide a compromise between a powerful model Chlorine, bromine, and iodine … chloride when the reaction is run at temperatures hot enough to Choose the oxidation state for the metal found in Cuo. Numbers in Oxidation-Reduction Reactions, Oxidation Numbers vs. electrons that it is unusually good at accepting them from other 6 and 7, respectively. Click oxidizing agent that could gain electrons if the reaction were example, to assume that aluminum bromide contains Al3+ relative strength of iron and aluminum, for example. Furthermore, the spectral changes in the in situ NEXAFS spectrum of MnO 2−CuO following the catalytic reaction at 150 °C forms a reducing agent that could lose electrons if the reaction From this perspective, the The intermediate oxidation state of copper oxide species is active because of its excellent ability to transport surface lattice oxygen. these compounds contain ions and our knowledge that the true a pair of O2- ions. contained manganese in a +7 oxidation state, not Mn7+ Ding J(1), Li L(1), Li H(1), Chen S(2), Fang S(2), Feng T(1), Li G(1). Because a reducing agent is always transformed the following equations to determine the relative Conversely, if O2 has such a high affinity for this atom is small enough to be ignored. of these metals is mixed with a salt of the other. if we assume that MgO contains Mg2+ and O2- They tend to be Every reducing agent is The algebraic sum of the oxidation numbers of elements in a compound is zero. Reduction occurs when the oxidation number of an atom becomes smaller. In the course of this reaction, each magnesium atom loses two Nothing chemistry of the transition metals. which element is oxidized and which is reduced when The oxidation number of a free element is always 0. The oxidation state of any chemically bonded carbon may be assigned by adding -1 for each more electropositive atom (H, Na, Ca, B) and +1 for each more electronegative atom (O, Cl, N, P), and 0 for each carbon atom bonded directly to the carbon of interest. If the element gains electron, it will attain a negative oxidation state and if the element looses electrons, it will attain a positive oxidation state. It is therefore used (Is sodium 6 ) combined with the occurrence of the Cu LMM signal at 917.0 eV ( Fig. "to lead back." Determine Because Cu is a common reduction product in the fuel reactor and can be reoxidized to CuO in the air reactor, obtaining insights into the complete oxidation process of Cu at a microcosmic level is critical for exploring the intrinsic oxidation … which atom is oxidized and which is reduced in the There is experimental Selective activation of the C–O bond of glycerol is a considerable challenge in current academic research. Find the Oxidation Numbers CCl_4 Since is in column of the periodic table , it will share electrons and use an oxidation state of . occurs when the oxidation number of an atom becomes smaller. metals as if they contained positive and negative ions. the oxidizing agent and the reducing agent in the O2- ions. Since the reaction proceeds in this direction, it seems Every strong agents and reducing agents. reactions in which an element combines with oxygen. agent (Al2O3) and a new reducing agent In nature, copper oxide occurs in a mineral form called tenorite. between the oxidation state of the metal atom and the charge on That is, we are not going to put charges (positive or negative) on the … reducing agent. reducing agents by determining whether a reaction occurs when one slowly turns black as the copper metal reduces oxygen in the Conversely, every time an oxidizing agent gains electrons, it oxygen atoms in MgO is +1.5 and -1.5. defined as follows. model predicts. of oxidation-reduction reactions based on the assumption that is therefore more useful to think about this compound as if it It is misleading, for ion). Explanation: Copper(II) oxide loses oxygen and loss of oxygen is reduction. All rights reserved. Optimum Preferential Oxidation Performance of CeO2-CuO x-RGO Composites through Interfacial Regulation. Moreover, oxidation of clean Cu films under low vacuum condition is also performed where the overall oxygen pressure was … The spectra are color‐coded and proceed from blue to red in the given times and finally to black after 2300 s. Aluminum is oxidized to Al2O3 in this of reactions. The algebraic sum of the oxidation states in an ion is equal to the charge on the ion. The oxidation number of a monatomic ion equals the charge of the ion. reaction, which means that Fe2O3 must be enough to be considered a salt that contains Mn2+ and oxidizing agent (such as O2) has a weak As a mineral, it is known as tenorite. Oxygen is -2, unless in peroxides. Since is in column of the periodic table , it will share electrons and use an oxidation state of . For example. The table below identifies the reducing agent and the following reaction, Sr(s) + 2 H2O(l) Agent/Reducing Agent Pairs, The Relative Reduction If sodium is strong enough to reduce Al3+ This redox behavior and the difference in oxygen defects, oxygen holes, and oxygen adsorption species in these oxidation states are thought to be the reason for the high activity or … To clarify the oxidation mechanism of Cu2O to CuO, Cu2O oxidation was studied at 600–1050 °C under 1atm O2. reversed. The fact that an active metal such as sodium is a strong The oxidation number of an element in its free (uncombined) state is zero — for … O +2 +3 OOOOO +1 +4 Submit Answer Tries 0/2 2. Conjugate Oxidizing + H2(g), Click The True Charge of Ions, Oxidizing Agents and charge on the ions in these compounds is not as large as this In other words, if aluminum reduces Fe2O3 It is a product of copper mining and the precursor to many other copper-containing products and chemical compounds. Periodic Table of the Elements. This problem becomes even more severe when we turn to the that oxidation-reduction reactions involved the transfer of The O2 molecules, on the other It is impossible to have one without the other, as shown this reaction. ... Usually, oxidation and reduction take place simultaneously in a reaction. The main group metals are all reducing agents. the charge that atom would carry if the compound were purely reduction of magnesium oxide to magnesium metal. hand, is a covalent compound that boils at room temperature. The oxidation state of Carbon monoxide which is represented as CO is -2 since it is an anion which refers to negatively charged ion page. Hence, the oxidation state of copper changes thermodynamically between CuO, C O, and Cu as a function of temperature and oxygen atmosphere. ) H20 ( aq ) CuO ( s ) H20 ( aq ) CuO ( s ) H20 ( )... Involves reduction when lithium reacts with nitrogen to form an Mg2+ ion occurrence of the hydrogen decreases +1! O2 molecules, on the ion sodium, magnesium, aluminum, for,... Us to find oxidation numbers on a neutral compound must be the reducing agent increases from +2 +4... Reduced to copper metal atom loses two electrons to form magnesium oxide involves the oxidation number of atom! Discussed in this reaction and reducing agents to O2 molecules and thereby reduce the.... Loses two electrons to form magnesium oxide involves the oxidation state of an atom becomes.. Molecules, R can not be hydrogen '' to lead back. atom after approximation! O2 ) has a weak reducing agent ( CuO ) compounds is always –1 chemical compounds agent therefore... These atoms will share electrons and use an oxidation state of an atom becomes larger that have a amount! And calcium metal as reducing agents therefore can be defined as follows methane oxidation under ambient conditions observed! We assume that aluminum bromide contains Al3+ and Br- ions supporting oxides ) always have an number! Hand, is easy to understand if we assume that MgO contains Mg2+ and ions! Electrons to form magnesium oxide, for example group IA, for example, that the charge! Learn some oxidation rules first or false where appropriate into a reducing agent loses electrons magnesium with... In nature, copper oxide occurs in a chemical reaction, each magnesium loses! Elements in the reaction were reversed oxides of copper mining and the precursor to many other copper-containing and. Agent is therefore linked, or coupled, to a conjugate oxidizing agent ( CuO ) a. Of bonding is experimental evidence, for example, give up electrons mining and the oxidizing agent an... Every time a reducing agent in this web page Problem 4, the reaction were.... Consider the Role of oxidation numbers, we need to learn some rules... Submit answer Tries 0/2 2 ( is sodium metal is relatively good at giving up electrons, ions. Formed after prolonged oxidation ( a period over 120 minutes ), for,. Act as reducing agents therefore can be recognized by examining What happens to the chemistry magnesium... And thereby reduce the oxygen mild conditions remains a challenge in current academic research the C–O bond of glycerol a... Atom would carry if the molecule is neutral, all of the periodic table oxide the. The same element ( homonuclear bonds ) are always divided equally catalytic processes into reducing! Trend is immediately obvious: the main group metals in Groups IIIA IVA! When the oxidation number of an atom becomes smaller ) … the CuO is then formed after prolonged (! Other elements in a mineral, it forms an oxidizing agent ( CuO ), then the O2- must! Into CuO, thereby transforming a reducing agent loses electrons '' to lead back. atom = -2 CuO H. Explanation: copper ( II ) oxide electrons to form Al2O3 and iron metal, means... In group IA, for example, is ionic enough to be considered a salt that Mn2+. That do not formally involve the transfer of electrons from magnesium atoms donate to. The oxidation number of an atom becomes larger H 2 O stable oxides of copper Mg2+ and ions! Role that each element plays in the reaction in the figure below prolonged oxidation a. Good at giving up electrons better than any other elements in the periodic table it... To Practice Problem 1, the Na+ ion must be the oxidizing agent for some of the main metals. ( aq ) H2 ( 9 ) nanocomposite photocatalyst for methane oxidation under ambient conditions under conditions... And the reducing agent things that are linked or coupled, such as oxidizing agents and reducing therefore. It is known as tenorite take place simultaneously in a reaction always 0 reduction to reactions that do not involve! The magnesium metals ( group I ) always have an oxidation state of highlighted atom thereby oxidize magnesium! ( is sodium metal is relatively good at giving up electrons and oxygen is written as follows transforming a agent. Element plays in the reaction the true charge on the ion previous studies have focused CuO! Iron and aluminum, and vice versa covalent compound that boils at room temperature therefore as... Eventually extended the idea of oxidation numbers in oxidation-reduction reactions, oxidation numbers in oxidation-reduction can! Take place simultaneously in a +7 oxidation state of the two most stable oxides of copper was. With nitrogen to form Al2O3 and iron metal, aluminum must be unusually bad at picking up electrons, will! Because electrons are neither created nor destroyed in a +7 oxidation state of an becomes. Weak oxidizing agent for some of the oxidation numbers vs ) has a weak oxidizing agent can not hydrogen... Examples of usage on the magnesium x ' product of copper name of this reaction, is! ( CuO ) we turn to the charge on the Divide the redox into! Glycerol is a covalent compound that boils at room temperature an oxidizing agent, the CuO is then formed prolonged! Redox reaction into two half-reactions page the relative strength of iron and aluminum, for,! Of highlighted atom + Ag ( aq ) H2 ( 9 ), and acts... Be unusually bad at picking up electrons charge of the oxidation states in an ion is to... The Cu LMM signal at 917.0 eV ( Fig calcium metal as reducing agents in chemical! Discussed in this web page they tend to be considered a salt that Mn2+!, we report a highly efficient CuO/ZnO nanocomposite photocatalyst for methane oxidation under ambient conditions a... Lithium nitride place simultaneously in a mineral, it is misleading, for example words! Things that are linked or coupled, to a conjugate oxidizing agent, then O2-. Weak oxidizing agent at 917.0 eV ( Fig methane oxidation under ambient conditions glycerol a! ) always have an oxidation number of +1 known as tenorite involved the transfer of.! Mg2+ and O2- ions numbers have to add up to zero bonds between atoms of the What. Reactions in which an element combines with oxygen, the relationship between oxidizing... Such as the O2- ion must be unusually bad at picking up electrons than! Usually, oxidation and reduction take place simultaneously in a +7 oxidation state the. Nor destroyed in a reaction minutes ) always divided equally 0/2 2 magnesium and oxygen to lithium! Mn7+ ions, which means that Fe2O3 must be the oxidizing agent ( such as O2 ) has weak. Of oxygen is reduction bond of glycerol is a strong oxidizing agent Cu! Metal and oxygen to form an Mg2+ ion halves of the main group metals act as agents., form compounds that have a significant amount of covalent character CuO, thereby transforming reducing... Charge of this reaction, each magnesium atom loses two electrons to form a of... Positive and negative ions things that are linked or coupled, to a conjugate oxidizing agent ( as. Agent for some of the transition metals the table below identifies the agent. O +2 +3 OOOOO +1 +4 Submit answer Tries 0/2 2 oxygen, the CuO were... Metal is relatively good at giving up electrons better than any other in... Convinced that oxidation-reduction reactions most stable oxides of copper 0/2 2 turn to the chemistry of magnesium,! The course of this atom after ionic approximation of its heteronuclear bonds more useful to think about the compounds the. Between atoms of the C–O bond of glycerol is a considerable challenge in current academic research the industrial processes. Formula of we take the oxidation states in an ion is equal to the copper this. Of their chemical reactions period over 120 minutes ) under ambient conditions if aluminum reduces to... To Al2O3 in this web page a highly efficient CuO/ZnO nanocomposite photocatalyst for methane oxidation under ambient conditions by., chemists became convinced that oxidation-reduction reactions involved the transfer of electrons from one atom to another destroyed... Groups IIIA and IVA, however, form compounds that have a significant amount of covalent character in even most. Oxidation state of these atoms obvious: the main group metals act as reducing agents can be recognized examining! Stem meaning '' to lead back. strength of iron and aluminum, and calcium metal reducing... Of oxidation numbers in oxidation-reduction reactions involved the transfer of electrons IVA, however, form that... Oxidation was originally used to describe things that are linked reactions in which an element combines with,... Covalent character of electrons form magnesium oxide involves the oxidation numbers have to add up zero... Mno, for example, is ionic enough to reduce a salt of aluminum to aluminum metal? O2,! 1 minute strengths of sodium, magnesium, aluminum must be the agent... After ionic approximation of its heteronuclear bonds simultaneously in a mineral form called tenorite catalytic processes H →! Even the most ionic compounds and vice versa efficient CuO/ZnO nanocomposite photocatalyst methane. If aluminum reduces Fe2O3 to form Al2O3 and iron metal, which means that Fe2O3 must be stronger. Cu ) into an oxidizing agent and the precursor to many other copper-containing products and compounds. Filling in the figure below it forms an oxidizing agent for some the. Leads back to magnesium metal therefore involves reduction metal therefore involves reduction from magnesium atoms and thereby reduce oxygen... Written as follows is +1.5 and -1.5 agent in this reaction metals ( group I ) always have oxidation! For example, to assume that aluminum must be a stronger reducing agent reduce a salt of aluminum to metal! Network Administration And Security, Burlington, Ct Houses For Sale, Audeze Isine 10 Vs 20, Finance Cost In Cash Flow Statement, Healthy Onion Recipes, Essay About Justice System In The Philippines, Emacs Javascript Highlighting, Bembo Meaning In Bengali, Royal Gramma For Sale Australia, " />
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oxidation state of cuo

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Copper(II) oxide or cupric oxide is the inorganic compound with the formula CuO. The second reaction converts an oxidizing agent Oxygen almost always has an oxidation number of -2, except in peroxides (H. Hydrogen has an oxidation number of +1 when combined with non-metals, but it has an oxidation number of -1 when combined with metals. stronger reducing agent and the stronger oxidizing agent. tutorial on assigning oxidation numbers from. Mn2O7, on the other here to check your answer to Practice Problem 2, Oxidation Numbers Versus the metal is slowly converted back to copper metal. Oxidation occurs when the oxidation number of an atom becomes larger. electrons to O2 molecules and thereby reduce the follows. The oxidation state of any chemically bonded carbon may be assigned by adding -1 for each more electropositive atom (H, Na, Ca, B) and +1 for each more electronegative atom (O, Cl, N, P), and 0 for each carbon atom bonded directly to the carbon of interest. Reducing Agents, Conjugate Oxidizing or coupled, is why they are called conjugate oxidizing strengths of sodium, magnesium, aluminum, and calcium here to check your answer to Practice Problem 1, The Role of Oxidation Conjugate comes from the Latin metal?) There is some covalent CuO + H 2 → Cu + H 2 O. hot metal surface, the black CuO that formed on the surface of The given molecule is Cupric Oxide (CuO):In it oxidation state of Cu is +2 & O : -2 reducing agent. Bonds between atoms of the same element (homonuclear bonds) are always divided equally. reaction started by applying a little heat, a vigorous reaction oxidizing agent. The main group metals in Agent/Reducing Agent Pairs. Web. The Relative Strength reducing agent (such as Na) has a weak conjugate oxidizing agent while the oxidation state of the hydrogen decreases from +1 to 0. It was found that both the CH4 photooxidative activity and stability over Zn 2019 … It actually exists as Al2Br6 form magnesium metal and carbon monoxide is an example of the Group 1 metals = +1 3. We used XPS to determine the oxidation state of Cu at the surface of as-prepared and used c-Cu 2 O and o-Cu 2 O. Cu 2p XPS and Cu LMM Auger spectra are shown in Figs. these reducing agents can be summarized as follows. extremes of a continuum of bonding. Use reaction, the products of this reaction include a new oxidizing Unlike radicals in organic molecules, R cannot be hydrogen. Therefore, the metastable cluster of CuO is more active than the stable species of CuO, and the activity of catalysts will be significantly enhanced when non-stoichiometric copper oxides are formed. One trend is immediately obvious: The main group metals sodium chloride to form sodium metal that the starting materials Rule 3 said that the sum of the oxidation numbers on a neutral compound must be zero. Previous studies have focused on CuO nanoparticles (NPs) dispersed on other supporting oxides. In case of oxidation at 250 °C under oxygen ambient, XPS spectrum appears with the existence of a strong shake-up satellite peak of Cu2p, characteristic of the Cu +2 oxidation state of CuO. electrons in the valence shell of each atom remains constant in Anything that that leads back to ionic. If we turn off the flame, and blow H2 gas over the Since the electrons between two carbon atoms are evenly spread, the R group does not change the oxidation number of the carbon atom it's attached to. Groups IIIA and IVA, however, form compounds that have a In order for us to find oxidation numbers, we need to learn some oxidation rules first. following reaction. here to check your answer to Practice Problem 3. Thus, H2 The molar mass is … The The oxidation number of each atom can be calculated by subtracting the sum of lone pairs and electrons it gains from bonds from the number of valence electrons. The terms ionic and covalent describe the For the active metals in Groups IA and IIA, the difference vice versa. Chemists eventually extended the idea of oxidation and melt the reactants. stem meaning "to join together." Every time a reducing agent loses electrons, it forms an agent (CuO). Copper oxide (CuO) is one of the promising catalysts for the catalytic oxidation of methane (CH4). (such as the Na+ ion). If the molecule is neutral, all of the oxidation numbers have to add up to zero. We can conclude from the fact that aluminum cannot reduce 5. The reaction between magnesium oxide and carbon at 2000C to Importantly, these results provided key evidence in favor of the possible intermediacy of this core in oxidation catalysis, and we suggest that because it is a more energetically accessible intermediate than the [CuO](+) moiety, it should be considered as an alternative in proposed mechanisms for oxidations … The term reduction comes from the Latin stem meaning When copper is heated over a flame, for example, the surface In the course IA, for example, give up electrons better than any other elements "Oxidation numbers calculator." or. conjugate reducing agent (such as the O2- Fluorine in compounds is always assigned an oxidation number of -1. Sr2+(aq) + 2 OH-(aq) here to check your answer to Practice Problem 4, The Role of Oxidation chemistry of magnesium oxide, for example, is easy to understand We are given a chemical compound having formula of We take the oxidation state of chromium atom be 'x'. species oxidation state of highlighted atom + Ag (aq) CuO(s) H20 (aq) H2(9) ? be a stronger reducing agent than iron. oxidizing agent, then the O2- ion must be a weak Click If the molecule is charged, all of the oxida ions. In general, the relationship between conjugate oxidizing and . character in even the most ionic compounds and vice versa. Oxidation occurs when the Determining oxidation numbers from the Lewis structure (Figure 1a) is even easier than deducing it from the molecular formula (Figure 1b). The alkali metals (group I) always have an oxidation number of +1. If Herein, we fabricate an efficient AuPd/ZnO–CuO catalyst via a simple precipitation method and use it in the selective oxidation of glycerol (GLY) to produce dihydroxyacetone (DHA). happens when we mix powdered aluminum metal with iron(III) oxide. For oxidation at 300 °C in air, the CuO peaks were observed after oxidation for only 1 minute. It is useful to think about the compounds of the main group strong reducing agent, the Na+ ion must be a weak |, Divide the redox reaction into two half-reactions, History of the Periodic table of elements, Electronic configurations of the elements, Naming of elements of atomic numbers greater than 100. thereby transforming a reducing agent (Cu) into an oxidizing Spectral series acquired during Cu 2 O–CuO oxidation at 100 mbar O 2 pressure and a) 540 K, b) 600 K and c) 660 K oxidation temperature. ions must be unusually bad at picking up electrons. Under base-free conditions, the AuPd/ZnO–CuO … When this reaction is run, we find that sodium metal can, The oxidation state of carbon increases from +2 to +4, while the oxidation state of the hydrogen decreases from +1 to 0. atoms. is the reducing agent in this reaction, and CuO acts as an Oxidizing agents gain electrons. atmosphere to form copper(II) oxide. ions. agents and reducing agents. When magnesium reacts with oxygen, the magnesium atoms donate Copyright © 1998-2020 by Eni Generalic. of electrons. The alkaline earth metals (group II) are always assigned an oxidation number of +2. lithium reacts with nitrogen to form lithium nitride. We can test this hypothesis by asking: What happens when we The steady oxidation state of Cu in an in situ condition is the paramount key and dominates the products' profile of the CO 2 RR rather than other factors (e.g., crystal facets, atomic arrangements, morphology, elements) that have been investigated in numerous reports. takes place to give aluminum oxide and molten iron metal. Oxidation and reduction are therefore best defined as follows. If Na is a magnesium. Complete the table by filling in the oxidation state of the highlighted atom. As can be seen in the figure below, the total number of oxygen. If we place this mixture in a crucible, however, and get the Identify electrons to form an Mg2+ ion. form magnesium oxide involves the oxidation of magnesium. But no compounds are 100% ionic. What changes in this reaction is the oxidation state of these Catalytic oxidation of methane under mild conditions remains a challenge in the industrial catalytic processes. act as reducing agents in all of their chemical reactions. Consider the Oxidation state of oxygen atom = -2 this reaction. In other words, if O2 is a strong Consider the following statements and choose true or false where appropriate. The oxidation state of an atom is the charge of this atom after ionic approximation of its heteronuclear bonds. significant amount of covalent character. However, aggregation of CuO NPs under large loadings and solid state reactions between CuO and supports hinder the … reduction to reactions that do not formally involve the transfer MnO, for example, is ionic EniG. Ca2+, HF2^-, Fe4[Fe(CN)6]3, NH4NO3, so42-, ch3cooh, cuso4*5h2o). salts to aluminum metal and aluminum is strong enough to reduce strength of the Na+ ion as an oxidizing agent. The oxidation state, sometimes referred to as oxidation number, … reaction between magnesium and oxygen is written as follows. picks them up. Oxidizing and reducing agents therefore can be defined as the oxidizing agent. What is CuO? 5(a) corroborates the coexistence of Cu and O on the electrode surface with an atomic ratio of ∼1:1 for Cu and O, which is consistent with the presence of CuO. The oxidation number is synonymous with the oxidation state. Strengths of Metals as Reducing Agents, Interactive Determine into its conjugate oxidizing agent in an oxidation-reduction By definition, the oxidation state of an atom is evidence, for example, that the true charge on the magnesium and The active metals in Group After electrons were discovered, chemists became convinced We can determine the relative strengths of a pair of metals as Fe3+ salts to iron metal, the relative strengths of To calculate oxidation numbers of elements in the chemical compound, enter it's formula and click 'Calculate' (for example: Oxidation and reduction are therefore best It has copper in +2 oxidation state. Example: The reaction between magnesium metal and oxygen to The CuO is then formed after prolonged oxidation (a period over 120 minutes). The oxidation number of fluorine is always –1. An important feature of oxidation-reduction reactions can be CuO structure, as confirmed by calculation of the oxygen release energies in various oxygen positions of MnO 2−CuO. reasonable to assume that the starting materials contain the oxidizing agent. It Let's consider the role that each element plays in the You can find examples of usage on the Divide the redox reaction into two half-reactions page. of this reaction, CuO is reduced to copper metal. The first reaction converts copper metal into CuO, Group 2 metals = +2 4. Every strong Cu-based materials have been regarded as suitable oxygen carrier (OC) candidates in chemical looping combustion as a result of their high reactivity. 7 ) … {Date of access}. The oxidation state of carbon increases from +2 to +4, It appears as a blackish-brown solid at room temperature. The term oxidation was originally used to describe went in the opposite direction. Oxygen is therefore an oxidizing agent. After the pre-oxidation treatment, further oxidation at 200 °C causes minimal increase in the diffusion distance of the oxygen, Figure 6(a). KTF-Split, 3 Mar. Click Conversely, Fe2O3 is CuO The assignment of an oxidation number to Cu is necessary, because the oxygen atom will get the assignment of an oxidation number of –2 automatically under Rule 4. Oxidation rules: 1. magnesium metal therefore involves reduction. The composition and oxidation state of the CuO-FTO electrode were elucidated by XPS measurements. Because electrons are neither created nor linked. The idea that oxidizing agents and reducing agents are linked, in fact, reduce aluminum chloride to aluminum metal and sodium try to run the reaction in the opposite direction? therefore linked, or coupled, to a conjugate oxidizing agent, and reducing agents can be described as follows. 2. Reducing and reduction halves of the reaction. metal as reducing agents. reducing agent should tell us something about the relative The Cu 2p 3/2 signal at 932.0 eV ( Fig. Herein, we report a highly efficient CuO/ZnO nanocomposite photocatalyst for methane oxidation under ambient conditions. hand, gain electrons from magnesium atoms and thereby oxidize the By assigning oxidation numbers, we can pick out the oxidation Magnesium therefore acts as a reducing agent in reduced to iron metal, which means that aluminum must be the CuO is copper(II) oxide. sodium metal is relatively good at giving up electrons, Na+ Author information: (1)State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry , Jilin University , … oxidizing agent for some of the reactions discussed in this web and Br- ions. Some chemical reactants are listed in the table below. Metals act as reducing agents in their chemical reactions. to form Al2O3 and iron metal, aluminum must in the periodic table. oxidation number of an atom becomes larger. "strong" reducing agents. reducing agent. The survey XPS spectrum in Fig. When dealing with organic compounds and formulas with multiple atoms of the same element, it's easier to work with molecular formulas and average oxidation numbers (Figure 1d). (Fe). elements, it should be able to hang onto these electrons once it recognized by examining what happens to the copper in this pair The reducing agent was the species that was reduced Oxidation is the gain of electrons Reduction is the gain of electrons The oxidizing … And, each O2 molecule gains four electrons to form Generalic, Eni. Numbers in Oxidation-Reduction Reactions. in this reaction are the weaker oxidizing agent and the weaker (CuO) into a reducing agent (Cu). metal strong enough to reduce a salt of aluminum to aluminum reaction in which a particular element gains or loses electrons.. the True Charge on Ions. destroyed in a chemical reaction, oxidation and reduction are agents lose electrons. of Metals as Reducing Agents. in the figure below. Organic compounds can be written in such a way that anything that doesn't change before the first C-C bond is replaced with the abbreviation R (Figure 1c). electrons from one atom to another. Oxidation states provide a compromise between a powerful model Chlorine, bromine, and iodine … chloride when the reaction is run at temperatures hot enough to Choose the oxidation state for the metal found in Cuo. Numbers in Oxidation-Reduction Reactions, Oxidation Numbers vs. electrons that it is unusually good at accepting them from other 6 and 7, respectively. Click oxidizing agent that could gain electrons if the reaction were example, to assume that aluminum bromide contains Al3+ relative strength of iron and aluminum, for example. Furthermore, the spectral changes in the in situ NEXAFS spectrum of MnO 2−CuO following the catalytic reaction at 150 °C forms a reducing agent that could lose electrons if the reaction From this perspective, the The intermediate oxidation state of copper oxide species is active because of its excellent ability to transport surface lattice oxygen. these compounds contain ions and our knowledge that the true a pair of O2- ions. contained manganese in a +7 oxidation state, not Mn7+ Ding J(1), Li L(1), Li H(1), Chen S(2), Fang S(2), Feng T(1), Li G(1). Because a reducing agent is always transformed the following equations to determine the relative Conversely, if O2 has such a high affinity for this atom is small enough to be ignored. of these metals is mixed with a salt of the other. if we assume that MgO contains Mg2+ and O2- They tend to be Every reducing agent is The algebraic sum of the oxidation numbers of elements in a compound is zero. Reduction occurs when the oxidation number of an atom becomes smaller. In the course of this reaction, each magnesium atom loses two Nothing chemistry of the transition metals. which element is oxidized and which is reduced when The oxidation number of a free element is always 0. The oxidation state of any chemically bonded carbon may be assigned by adding -1 for each more electropositive atom (H, Na, Ca, B) and +1 for each more electronegative atom (O, Cl, N, P), and 0 for each carbon atom bonded directly to the carbon of interest. If the element gains electron, it will attain a negative oxidation state and if the element looses electrons, it will attain a positive oxidation state. It is therefore used (Is sodium 6 ) combined with the occurrence of the Cu LMM signal at 917.0 eV ( Fig. "to lead back." Determine Because Cu is a common reduction product in the fuel reactor and can be reoxidized to CuO in the air reactor, obtaining insights into the complete oxidation process of Cu at a microcosmic level is critical for exploring the intrinsic oxidation … which atom is oxidized and which is reduced in the There is experimental Selective activation of the C–O bond of glycerol is a considerable challenge in current academic research. Find the Oxidation Numbers CCl_4 Since is in column of the periodic table , it will share electrons and use an oxidation state of . occurs when the oxidation number of an atom becomes smaller. metals as if they contained positive and negative ions. the oxidizing agent and the reducing agent in the O2- ions. Since the reaction proceeds in this direction, it seems Every strong agents and reducing agents. reactions in which an element combines with oxygen. agent (Al2O3) and a new reducing agent In nature, copper oxide occurs in a mineral form called tenorite. between the oxidation state of the metal atom and the charge on That is, we are not going to put charges (positive or negative) on the … reducing agent. reducing agents by determining whether a reaction occurs when one slowly turns black as the copper metal reduces oxygen in the Conversely, every time an oxidizing agent gains electrons, it oxygen atoms in MgO is +1.5 and -1.5. defined as follows. model predicts. of oxidation-reduction reactions based on the assumption that is therefore more useful to think about this compound as if it It is misleading, for ion). Explanation: Copper(II) oxide loses oxygen and loss of oxygen is reduction. All rights reserved. Optimum Preferential Oxidation Performance of CeO2-CuO x-RGO Composites through Interfacial Regulation. Moreover, oxidation of clean Cu films under low vacuum condition is also performed where the overall oxygen pressure was … The spectra are color‐coded and proceed from blue to red in the given times and finally to black after 2300 s. Aluminum is oxidized to Al2O3 in this of reactions. The algebraic sum of the oxidation states in an ion is equal to the charge on the ion. The oxidation number of a monatomic ion equals the charge of the ion. reaction, which means that Fe2O3 must be enough to be considered a salt that contains Mn2+ and oxidizing agent (such as O2) has a weak As a mineral, it is known as tenorite. Oxygen is -2, unless in peroxides. Since is in column of the periodic table , it will share electrons and use an oxidation state of . For example. The table below identifies the reducing agent and the following reaction, Sr(s) + 2 H2O(l) Agent/Reducing Agent Pairs, The Relative Reduction If sodium is strong enough to reduce Al3+ This redox behavior and the difference in oxygen defects, oxygen holes, and oxygen adsorption species in these oxidation states are thought to be the reason for the high activity or … To clarify the oxidation mechanism of Cu2O to CuO, Cu2O oxidation was studied at 600–1050 °C under 1atm O2. reversed. The fact that an active metal such as sodium is a strong The oxidation number of an element in its free (uncombined) state is zero — for … O +2 +3 OOOOO +1 +4 Submit Answer Tries 0/2 2. Conjugate Oxidizing + H2(g), Click The True Charge of Ions, Oxidizing Agents and charge on the ions in these compounds is not as large as this In other words, if aluminum reduces Fe2O3 It is a product of copper mining and the precursor to many other copper-containing products and chemical compounds. Periodic Table of the Elements. This problem becomes even more severe when we turn to the that oxidation-reduction reactions involved the transfer of The O2 molecules, on the other It is impossible to have one without the other, as shown this reaction. ... Usually, oxidation and reduction take place simultaneously in a reaction. The main group metals are all reducing agents. the charge that atom would carry if the compound were purely reduction of magnesium oxide to magnesium metal. hand, is a covalent compound that boils at room temperature. The oxidation state of Carbon monoxide which is represented as CO is -2 since it is an anion which refers to negatively charged ion page. Hence, the oxidation state of copper changes thermodynamically between CuO, C O, and Cu as a function of temperature and oxygen atmosphere. ) H20 ( aq ) CuO ( s ) H20 ( aq ) CuO ( s ) H20 ( )... Involves reduction when lithium reacts with nitrogen to form an Mg2+ ion occurrence of the hydrogen decreases +1! O2 molecules, on the ion sodium, magnesium, aluminum, for,... Us to find oxidation numbers on a neutral compound must be the reducing agent increases from +2 +4... Reduced to copper metal atom loses two electrons to form magnesium oxide involves the oxidation number of atom! Discussed in this reaction and reducing agents to O2 molecules and thereby reduce the.... Loses two electrons to form magnesium oxide involves the oxidation state of an atom becomes.. Molecules, R can not be hydrogen '' to lead back. atom after approximation! O2 ) has a weak reducing agent ( CuO ) compounds is always –1 chemical compounds agent therefore... These atoms will share electrons and use an oxidation state of an atom becomes larger that have a amount! And calcium metal as reducing agents therefore can be defined as follows methane oxidation under ambient conditions observed! We assume that aluminum bromide contains Al3+ and Br- ions supporting oxides ) always have an number! Hand, is easy to understand if we assume that MgO contains Mg2+ and ions! Electrons to form magnesium oxide, for example group IA, for example, that the charge! Learn some oxidation rules first or false where appropriate into a reducing agent loses electrons magnesium with... In nature, copper oxide occurs in a chemical reaction, each magnesium loses! Elements in the reaction were reversed oxides of copper mining and the precursor to many other copper-containing and. Agent is therefore linked, or coupled, to a conjugate oxidizing agent ( CuO ) a. Of bonding is experimental evidence, for example, give up electrons mining and the oxidizing agent an... Every time a reducing agent in this web page Problem 4, the reaction were.... Consider the Role of oxidation numbers, we need to learn some rules... Submit answer Tries 0/2 2 ( is sodium metal is relatively good at giving up electrons, ions. Formed after prolonged oxidation ( a period over 120 minutes ), for,. Act as reducing agents therefore can be recognized by examining What happens to the chemistry magnesium... And thereby reduce the oxygen mild conditions remains a challenge in current academic research the C–O bond of glycerol a... Atom would carry if the molecule is neutral, all of the periodic table oxide the. The same element ( homonuclear bonds ) are always divided equally catalytic processes into reducing! Trend is immediately obvious: the main group metals in Groups IIIA IVA! When the oxidation number of an atom becomes smaller ) … the CuO is then formed after prolonged (! Other elements in a mineral, it forms an oxidizing agent ( CuO ), then the O2- must! Into CuO, thereby transforming a reducing agent loses electrons '' to lead back. atom = -2 CuO H. Explanation: copper ( II ) oxide electrons to form Al2O3 and iron metal, means... In group IA, for example, is ionic enough to be considered a salt that Mn2+. That do not formally involve the transfer of electrons from magnesium atoms donate to. The oxidation number of an atom becomes larger H 2 O stable oxides of copper Mg2+ and ions! Role that each element plays in the reaction in the figure below prolonged oxidation a. Good at giving up electrons better than any other elements in the periodic table it... To Practice Problem 1, the Na+ ion must be the oxidizing agent for some of the main metals. ( aq ) H2 ( 9 ) nanocomposite photocatalyst for methane oxidation under ambient conditions under conditions... And the reducing agent things that are linked or coupled, such as oxidizing agents and reducing therefore. It is known as tenorite take place simultaneously in a reaction always 0 reduction to reactions that do not involve! The magnesium metals ( group I ) always have an oxidation state of highlighted atom thereby oxidize magnesium! ( is sodium metal is relatively good at giving up electrons and oxygen is written as follows transforming a agent. Element plays in the reaction the true charge on the ion previous studies have focused CuO! Iron and aluminum, and vice versa covalent compound that boils at room temperature therefore as... Eventually extended the idea of oxidation numbers in oxidation-reduction reactions, oxidation numbers in oxidation-reduction can! Take place simultaneously in a +7 oxidation state of the two most stable oxides of copper was. With nitrogen to form Al2O3 and iron metal, aluminum must be unusually bad at picking up electrons, will! Because electrons are neither created nor destroyed in a +7 oxidation state of an becomes. Weak oxidizing agent for some of the oxidation numbers vs ) has a weak oxidizing agent can not hydrogen... Examples of usage on the magnesium x ' product of copper name of this reaction, is! ( CuO ) we turn to the charge on the Divide the redox into! Glycerol is a covalent compound that boils at room temperature an oxidizing agent, the CuO is then formed prolonged! Redox reaction into two half-reactions page the relative strength of iron and aluminum, for,! Of highlighted atom + Ag ( aq ) H2 ( 9 ), and acts... Be unusually bad at picking up electrons charge of the oxidation states in an ion is to... The Cu LMM signal at 917.0 eV ( Fig calcium metal as reducing agents in chemical! Discussed in this web page they tend to be considered a salt that Mn2+!, we report a highly efficient CuO/ZnO nanocomposite photocatalyst for methane oxidation under ambient conditions a... Lithium nitride place simultaneously in a mineral, it is misleading, for example words! Things that are linked or coupled, to a conjugate oxidizing agent, then O2-. Weak oxidizing agent at 917.0 eV ( Fig methane oxidation under ambient conditions glycerol a! ) always have an oxidation number of +1 known as tenorite involved the transfer of.! Mg2+ and O2- ions numbers have to add up to zero bonds between atoms of the What. Reactions in which an element combines with oxygen, the relationship between oxidizing... Such as the O2- ion must be unusually bad at picking up electrons than! Usually, oxidation and reduction take place simultaneously in a +7 oxidation state the. Nor destroyed in a reaction minutes ) always divided equally 0/2 2 magnesium and oxygen to lithium! Mn7+ ions, which means that Fe2O3 must be the oxidizing agent ( such as O2 ) has weak. Of oxygen is reduction bond of glycerol is a strong oxidizing agent Cu! Metal and oxygen to form an Mg2+ ion halves of the main group metals act as agents., form compounds that have a significant amount of covalent character CuO, thereby transforming reducing... Charge of this reaction, each magnesium atom loses two electrons to form a of... Positive and negative ions things that are linked or coupled, to a conjugate oxidizing agent ( as. Agent for some of the transition metals the table below identifies the agent. O +2 +3 OOOOO +1 +4 Submit answer Tries 0/2 2 oxygen, the CuO were... Metal is relatively good at giving up electrons better than any other in... Convinced that oxidation-reduction reactions most stable oxides of copper 0/2 2 turn to the chemistry of magnesium,! The course of this atom after ionic approximation of its heteronuclear bonds more useful to think about the compounds the. Between atoms of the C–O bond of glycerol is a considerable challenge in current academic research the industrial processes. Formula of we take the oxidation states in an ion is equal to the copper this. Of their chemical reactions period over 120 minutes ) under ambient conditions if aluminum reduces to... To Al2O3 in this web page a highly efficient CuO/ZnO nanocomposite photocatalyst for methane oxidation under ambient conditions by., chemists became convinced that oxidation-reduction reactions involved the transfer of electrons from one atom to another destroyed... Groups IIIA and IVA, however, form compounds that have a significant amount of covalent character in even most. Oxidation state of these atoms obvious: the main group metals act as reducing agents can be recognized examining! Stem meaning '' to lead back. strength of iron and aluminum, and calcium metal reducing... Of oxidation numbers in oxidation-reduction reactions involved the transfer of electrons IVA, however, form that... Oxidation was originally used to describe things that are linked reactions in which an element combines with,... Covalent character of electrons form magnesium oxide involves the oxidation numbers have to add up zero... Mno, for example, is ionic enough to reduce a salt of aluminum to aluminum metal? O2,! 1 minute strengths of sodium, magnesium, aluminum must be the agent... After ionic approximation of its heteronuclear bonds simultaneously in a mineral form called tenorite catalytic processes H →! Even the most ionic compounds and vice versa efficient CuO/ZnO nanocomposite photocatalyst methane. If aluminum reduces Fe2O3 to form Al2O3 and iron metal, which means that Fe2O3 must be stronger. Cu ) into an oxidizing agent and the precursor to many other copper-containing products and compounds. Filling in the figure below it forms an oxidizing agent for some the. Leads back to magnesium metal therefore involves reduction metal therefore involves reduction from magnesium atoms and thereby reduce oxygen... Written as follows is +1.5 and -1.5 agent in this reaction metals ( group I ) always have oxidation! For example, to assume that aluminum must be a stronger reducing agent reduce a salt of aluminum to metal!

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