Half life (t1∕2) of a first order reaction does not depend on initial concentration of the reactant [R0]. Therefore Statement I is true. Rate constant (k) of a first order reaction is given by &‌k=‌
2.303
t
‌log‌
[R0]
[R]
‌log‌
[R]
[R0]
=−(‌
k
2.303
)t ‌ Plot of ‌log‌
[R]
[R0]
‌ versus time is linear having ‌ ‌ slope ‌=−‌