Chemistry

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The order and molecularity of elementary reactions are the same. As a result of a single collision between two molecules or ions, a complicated process occurs. A reaction mechanism is a set of elementary reactions.

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Ans:No, the difference in potentials of the electrodes is measured. A reference electrode is to be taken while measuring the electrode potential of the electrode.

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Experimentally, the reaction's rate law can be calculated.

Step 1

2NO (g) + O₂ (g)→2NO₂ (g)

O₂ (g) is taken in excess

x molecules of NO number reacting with excess of O₂

r = k [NO]^x

Step 2

2NO (g) + O₂ (g)→2NO₂ (g)

When 2No (g)is taken in excess

Y molecules of O₂ reacting with excess of [NO]

rate = k [O₂]^y

rate = k [NO]^x [NO]^y

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Ans: The relation between Gibbs free energy and the emf of the cell is as follows;

ΔG=−nFE_cell

 E $°$ _cell s the cell potential

is the standard emf of the cell

Maximum work obtained from the galvanic cell is nFE $°$ _.

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Given: Order of the reaction = 0

We know that a zero order reaction is a chemical reaction that occurs regardless of the reactant's concentration.

The rate law of 2A + B→C is

r = k [A]⁰ [B]⁰

For a zero- order reaction

r = k

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A bimolecular reaction occurs when two particles collide. The product of the concentrations of both elements determines the rate of reaction. If one of the reactants is taken in substantial excess in such a way that its concentration seldom changes, a bimolecular reaction can be kinetically first order.

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Tell us about the pseudo-first-order reaction. It's the reaction with the highest true rate law, yet it behaves like a first order reaction, but it's more specifically a second order reaction.

As an example, consider the hydrolysis of an ester.

CH₃COOC₂CH₅ + H₂O→CH₃COOH + C₂H₅OH

rate = k [CH₃COOC₂H₅] [H₂O]… (constant)

k1 [CH₃COOC₂H₅]

k = k [H₂O] 

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Ans: (i) Cell 'B' will act as an electrolytic cell because to less value of E_cell The reactions occurring in the cell are as follows;

At anode: Zn²⁺ + 2e⁻ → Zn

At cathode: Cu (s) → Cu²⁺ + 2e⁻

(ii) Cell 'B' has a higher emf so it acts as a galvanic cell. The reactions are as follows;

At anode: Zn → Zn²⁺ + 2e−

At cathode: Cu²⁺ + 2e− → Cu

This is a Long Answer Type Question as classified in NCERT Exemplar

Average rate depends upon the change in concentration of reactants or products and the time taken for that change to occur. However, the average rate cannot be used to predict the rate of reaction at a particular instance as it would be constant for the time interval for which it is calculated. 

So, to express the rate at a particular moment of time we determine the instantaneous rate. Itis obtained when we consider the average rate at the smallest time interval say dt (i.e. when? t approaches zero).