What is the value of slope, if $\log _{10} \mathrm{~K}$ (y-axis) is plotted versus $1 / \mathrm{T}$ ( $x$-axis) for Arrhenius equation?

For the reaction, $A+3 B \longrightarrow 2 C$

rate of consumption of A is $1.4 \mathrm{~mol} \mathrm{~dm}^{-3} \mathrm{~sec}^{-1}$. Calculate rate of formation of C ?

In a first order reaction if concentartion of reactant drops from $0.8 \mathrm{~mol} \mathrm{~L}^{-1}$ to $0.4 \mathrm{~mol} \mathrm{~L}^{-1}$ in 15 minute. What is the time required to drop concentration from $0.1 \mathrm{~mol} \mathrm{~L}^{-1}$ to 0.025 mol $\mathrm{L}^{-1}$.

Calculate the time required for reactant to decrease the concentration from $100 \%$ to $20 \%$, if rate constant of first order reaction is 0.02303 hours $^{-1}$.