Chemical Kineti...

What is the half life of a radioactive substance if $$75%$$ of its given amount disintegrate in $$60\ min$$?

The decomposition of $$N_2O_5$$ is a first order reaction as with a rate constant of $$5\times 10^{-4}s^{-1}$$. If the initial concentration of $$N_2O_5$$ is 0.25 M, then calculate its concentration after 2 minutes. 
$$N_2O_5(g) \rightarrow 2NO_2(g) + \dfrac{1}{2}O_2(g)$$

When ln k is plotted against $${ 1 }/{ T }$$, the slope was found to be -10.7 $$\times $$ $${ 10 }^{ 3 }$$ K, activation energy for the reaction would be :

The slope in the activation energy curve is 5.42 $$\times$$ $$10^{3}$$ . The value of the activation energy is approximately

For zero  order reaction, A$$ \to $$,a graph of rate vs time has slope equal to:( where k$$=$$rate of reaction)

$$3/4\ th$$ of first order reaction was completed in $$32\ min, 15/16$$ the part will be completed in ?

The rate expression for a reaction for a reaction is $$ \dfrac{-dC}{dt}=\dfrac {\alpha C_0}{1+\beta C_0}$$ where $$\alpha,\beta$$ are constants and C is the concentration of reactant at time 't'. The half -life for this reaction is ?

For the first order reaction $$(C=C_{0}e^{-k})$$ and $$T_{av}=K_{1}^{-1}$$. After two average lives, concentration of the reactant is reduced to? 

The decomposition of $$NH_3$$ on platinum surface is zero order reaction. What are the rates of production of $$N_2$$ and $$H_2$$ if $$K= 2.5\times 10^{-4} mol^{-1} L s^{-1}$$?

The rate constant of a reaction increased by $$5%$$ when temperature is raised from $$27^{o}$$ to $$28^{o}\ C$$. The activation energy of the reaction is $$(\log\ 7=0.8450)$$