For kinetic study of the reaction of iodide ion with $$\mathrm{H}_{2} \mathrm{O}_{2}$$ at room temperature :

(A) Always use freshly prepared starch solution.

(B) Always keep the concentration of sodium thiosulphate solution less than that of KI solution.

(C) Record the time immediately after the appearance of blue colour.

(D) Record the time immediately before the appearance of blue colour.

(E) Always keep the concentration of sodium thiosulphate solution more than that of KI solution.

Choose the correct answer from the options given below :

At $$30^{\circ} \mathrm{C}$$, the half life for the decomposition of $$\mathrm{AB}_{2}$$ is $$200 \mathrm{~s}$$ and is independent of the initial concentration of $$\mathrm{AB}_{2}$$. The time required for $$80 \%$$ of the $$\mathrm{AB}_{2}$$ to decompose is

Given: $$\log 2=0.30$$ $$\quad \log 3=0.48$$

For a first order reaction, the time required for completion of 90% reaction is 'x' times the half life of the reaction. The value of 'x' is

(Given : ln 10 = 2.303 and log 2 = 0.3010)

Which one of the following given graphs represents the variation of rate constant (k) with temperature (T) for an endothermic reaction?