Calculate the amount of reactant in percent that remains after 60 minutes involved in first order reaction. $$\left(\mathrm{k}=0.02303\right.$$ minute $$\left.^{-1}\right)$$

The rate for reaction $$\mathrm{A}+\mathrm{B} \rightarrow$$ product, is $$1.8 \times 10^{-2} \mathrm{~mol} \mathrm{~dm}^{-3} \mathrm{~s}^{-1}$$. Calculate the rate constant if the reaction is second order in $$\mathrm{A}$$ and first order in $$\mathrm{B}$$. ($$[\mathrm{A}]=0.2 \mathrm{M} ;[\mathrm{B}]=0.1 \mathrm{M}$$)

For the reaction $$\mathrm{N}_{2(\mathrm{~g})}+3 \mathrm{H}_{2(\mathrm{~g})} \rightarrow 2 \mathrm{NH}_{3(\mathrm{~g})}$$, rate of disappearance of $$\mathrm{N}_{2(\mathrm{~g})}$$ is $$2.22 \times 10^{-3} \mathrm{~mol} \mathrm{~dm}^{-3}$$. What is the rate of appearance of $$\mathrm{NH}_{3(\mathrm{~g})}$$ ?

Find the rate constant of first order reaction in second having half life of 2.5 hours.