Calculate the rate constant of the first order reaction if $$80 \%$$ of the reactant reacted in 15 minute.

Calculate the degree of dissociation of $$0.01 \mathrm{~M}$$ acetic acid at $$25^{\circ} \mathrm{C}\left[\Lambda_{\mathrm{c}}=15.0 \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1}\right.$$ and $$\left.\Lambda_0=300 \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1}\right]$$

Which element from following does NOT exhibit spin only magnetic moment in +3 state?

Identify the final product formed on ammonolysis of benzyl chloride followed by the reaction with two moles of $$\mathrm{CH}_3 \mathrm{I}$$.