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प्रश्न
Define ‘redox reaction’. Give one example.
What is redox reaction? Explain with one example
उत्तर १
When oxidation and reduction occur simultaneously in a given chemical reaction, it is known as a redox reaction.
Example of a redox reaction:
Reduction Oxidation
BaSO4 +4C → BaS+4CO
उत्तर २
The reaction in which simultaneous oxidation and reduction take place is called a redox reaction
Cu+2 + Zn → Zn+2 + Cu
in the above reaction, copper undergoes reduction whereas Zn undergoes oxidation.
Therefore the reaction is redox reaction.
उत्तर ३
The reaction in which one substance gets oxidised and other gets reduced is known as redox reaction.
Example:
ZnO + C → Zn + CO
Here, C is oxidised to CO because oxygen is being added and ZnO is reduced to Zn because oxygen is being removed. Therefore, it is a redox reaction.
संबंधित प्रश्न
A shiny brown-coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black-colored compound formed.
What is an oxidation reaction? Identify in the following reaction (i) the substance oxidised, and (ii) the substance reduced:
ZnO + C → Zn + CO
Fill in the following blanks with suitable words:
The addition of oxygen to a substance is called ......... whereas removal of oxygen is called ........
Fill in the following blanks with suitable words:
The addition of hydrogen to a substance is called ........ whereas removal of hydrogen is called .......
Give an example of an oxidation reaction.
Is oxidation an exothermic or an endothermic reaction?
Explain reduction in terms of gain or loss of oxygen with one example.
When copper powder is heated strongly in air, it forms copper oxide. Write a balanced chemical equation for this reaction. Name (i) substance oxidised, and (ii) substance reduced.
Define oxidation in terms of gain or loss of hydrogen with one example.
The process of respiration is:
(a) an oxidation reaction which is endothermic
(b) a reduction reaction which is exothermic
(c) a combination reaction which is endothermic
(d) an oxidation reaction which is exothermic
You are given the following chemical equation:
Mg (s) + CuO (s) → MgO (s) + Cu (s)
This equation represents:
(a) decomposition reaction as well as displacement reaction
(b) combination reaction as well as double displacement reaction
(c) redox reaction as well as displacement reaction
(d) double displacement reaction as well as redox reaction
Name the following:
The process in which oxygen is added or hydrogen is removed.
Define redox reaction.
Identify from the following reaction the reactants that undergo oxidation and reduction.
2Ag2O → 4 Ag + O2 ↑
Identify from the reaction the reactants that undergo oxidation and reduction.
2Mg + O2 → 2MgO
Identify from the reaction the reactants that undergo oxidation and reduction.
\[\ce{NiO + H2 -> Ni + H2O}\]
Explain the following in term of gain or loss of oxygen with two examples.
Oxidation
Explain the following in term of gain or loss of oxygen with two examples.
Reduction
Compare hydrogen with alkali metals on the basis of:
Oxide formation
In what respect does hydrogen differ from:
alkali metals
Is it essential that oxidation and reduction must occur side by side in a chemical reaction? Explain
State, giving reason, whether the substances printed in bold letters have been oxidized or reduced.
H2S + Cl2→ 2HCl + S
State whether the following conversion is oxidation or reduction:
PbO2 + SO2→ PbSO4
Name:
an oxidizing agent that does not contain oxygen.
Name:
a substance that will reduce aqueous Iron(III)ions to iron(II)ions.
Name:
a liquid that is an oxidizing agent as well as a reducing agent.
Define Oxidation reaction.
State the condition and give balanced equation for the conversion of coke to water gas.
State what is oxidising agent. Give an example of oxidising agent in the gaseous, liquid, and solid form.
Give two test for an oxidising agent.
Oxidising agents are also called as ______ because they remove electrons form other substances.
Oxidation is a process which involves ____________.
The process of reduction involves ____________.
\[\ce{MnO2 + 4HCl -> + 2H2O + Cl2}\]
Identify the substance oxidized in the above equation.
Identify the oxidising agent (oxidant) in the following reactions
`"Pb"_3"O"_4 + 8"HCl" -> 3"PbCl"_2 + "Cl"_2 + 4"H"_2"O"`
Identify the oxidising agent (oxidant) in the following reactions
`3"Fe" + 4"H"_2"O" -> "Fe"_3"O"_4 + 4"H"_2`
Identify the oxidising agent (oxidant) in the following reactions.
`"CuO" + "H"_2 -> "Cu" + "H"_2"O"`
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
The temperature of the reaction mixture rises when aluminium (Al) is added.
Explain this observation giving suitable reason.
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
The reaction of sodium metal is found to be highly explosive
Explain this observation giving suitable reason.
Why do we store silver chloride in a dark coloured bottle?
A silver article generally turns black when kept in the open for a few days. The article when rubbed with toothpaste again starts shining.
- Why do silver articles turn black when kept in the open for a few days? Name the phenomenon involved.
- Name the black substance formed and give its chemical formula.
What is a redox reaction?
Identify the following reactions as oxidation/reduction/redox reaction
Zn + CuSO4 → Cu + ZnSO4
Find the oxidation number of the element in the following compound.
Mg in MgO
Answer the questions based on the equation below:
\[\ce{CH3 - CH2 - OH ->[{[O]}][K2Cr2O7/H2SO4] CH3 - COOH}\]
- What type of reaction is it?
- What is the role of the chemical written on the arrow?
- Give one example of one such type of chemical as in answer (b).
The metallic oxide which can be reduced by using common reducing agents is ______.
