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प्रश्न
Is it essential that oxidation and reduction must occur side by side in a chemical reaction? Explain
उत्तर
In a chemical reaction, if one substance is oxidised, the other substance must necessarily be reduced. This is because the electrons lost during oxidation are simultaneously gained during reduction and vice versa.
For example, Zinc reacts with copper sulphate to form zinc sulphate and copper.
CuSO4 + Zn → ZnSO4 + Cu
Cu + 2SO42- + Zn →Zn + 2SO42- + Cu
Writing the half reaction,
Zn → Zn2+ + 2e- (Oxidation)
Cu2+ + 2e-→ Cu (Reduction)
They occur simultaneously as
Cu2+ + Zn→ Zn2++ Cu
Thus, oxidation and reduction always occur simultaneously.
APPEARS IN
संबंधित प्रश्न
Explain the following in term Oxidation of gain or loss of oxygen with two example.
The electron releasing tendency of zinc is ______ than that of copper.
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.
Reduction
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Cu2+ → Cu + Zn 2+
Complete and balance the following equation:
Zn +_________________→ZnCl2 + H2
State a reason why, when hydrogen is passed over heated copper oxide, the resultant product formed, differs in colour from the original reactant.
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
Silver metal does not show any change
Explain this observation giving suitable reason.
When hydrogen gas is passed over black copper oxide, a reddish-coloured layer of copper is formed.
Answer the questions that follow based on this reaction.
- Write the equation.
- What type of reaction is it?
- Complete the blanks:
In this reaction, an oxygen atom goes away from CuO (copper oxide), which means that ______ of copper oxide takes place, whereas a hydrogen molecule takes up an oxygen atom and water (H2O) is formed, meaning ______ of hydrogen takes place.
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).
