Question

59. If 57% of a first order reaction was completed in 32 min., then 50% of the reaction was completed in (A) 24 min. (B) 8 min. (C) 16 min. (D) 4 min​

Answer 1

59. If 57% of a first order reaction was completed in 32 min., then 50% of the reaction was completed in (A) 24 min.?

For a first-order reaction, we have:

t(log75%)=2t(log50%)

Given: t(log75%)=32 min

Substituting the values in the above expression, we get-

32 min =2 t(log50%)

t(log50%)=16 mins

Hence, 50% of the reaction would have been completed in 16 mins.

Answer is option (c)16 min