A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy `E_(a)` Large the value of activation energy, smaller the value of rate constant `k`. Larger is the value of activation energy, greater is the effect of temperature rise on rate constant `k`. `E_(f) =` Activation energy of forward reaction `E_(b) =` Activation energy of backward reaction `Delta H = E_(f) - E_(b)` `E_(f) =` threshold energy In a hypothetical reaction `A rarr B`, the activation energies for the forward and backward reactions are `15` and `9 kJ mol^(-1)`, respectively. The potential energy of `A` is `10 kJ mol^(-1)`. Which of the following is wrong?A. The threshold energy of the reaction is `25 kJ`.B. The potential energy of `B` is `16 kJ`.C. The heat of reaction is `6 kJ`.D. The reaction is exothermic.

A colliison between reactant molecules must occur with a certain minim

1.	A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy `E_(a)` Large the value of activation energy, smaller the value of rate constant `k`. Larger is the value of activation energy, greater is the effect of temperature rise on rate constant `k`. `E_(f) =` Activation energy of forward reaction `E_(b) =` Activation energy of backward reaction `Delta H = E_(f) - E_(b)` `E_(f) =` threshold energy In a hypothetical reaction `A rarr B`, the activation energies for the forward and backward reactions are `15` and `9 kJ mol^(-1)`, respectively. The potential energy of `A` is `10 kJ mol^(-1)`. Which of the following is wrong?A. The threshold energy of the reaction is `25 kJ`.B. The potential energy of `B` is `16 kJ`.C. The heat of reaction is `6 kJ`.D. The reaction is exothermic.
Answer» Correct Answer - D `Delta H = E_(f) -E_(b) = 15-9 = 6 kJ mol^(-1)`, i.e., endothermic. THE `=E_(a(f)) + PE` of `A = 15 + 10 = 25 kJ` `PE` of `B = THE-E_(a(b)) = 25-9 = 16 kJ` So statements (a), (b) and (c ) are correct and (d) is wrong.

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