In a first order reaction, the concentration of the reactant decrease from 0.6 M to 0.3 M in 15 ~min . The time taken for the concentration to change from 0.1 M to 0.025 M in minutes is

Step-by-step solution

Since, concentration of the reactant decreases from 0.6 M to 0.3 M (i.e., halved) in 15 minutes, therefore half time for this reaction be 15 ~min . i.e. , t_ 1 / 2 =15 ~min Now for a first order reaction k= 0.693 t_ 1 / 2 = 0.693 15 ~min ⁻¹ Again, k= 2.303 t [A]₀ [A] aligned 0.693 15 & = 2.303 t 0.1 0.025 t & = 2.303 15 0.693 4 & = 2.303 15 0.693 0.6020=30 ~min aligned Alternate method Reaction is of first order with t_ 1 / 2 =15 ~min aligned 0.1 M 15 ~min 0.1 2 & =0.05 M 15 ~min 0.05 2 & =0.025 M aligned Total tim