Question

A first order reaction has a rate constant, 1.15 x 10^-3 s^-1 . How long will 5 g of this reactant take to reduce to 3 g?

Answer 1

Here, [R]₀ = 5g 

[R] = 3 g 

k = 1.15 x 10^-3 s^-1 As the reaction is of first order,