Question

75% of the fiest order reaction is completed in 32 minute ;when was the 50 %reaction completed​

Answer 1

Answer:

Let initial amount = A

after 32 minutes = 75% of A completed = 0.75A

we know , formula for 1st order reaction ,

K = 2.303/t log[ initial ]/[final]

= 2.303/32 log{ A/(A - 0.75A)}

={2.303/32}× log4 --------(1)

for half life , formula is

T½ = 2.303/K log2

put K ={2.303/32} × log4

T½ = 2.303/[{2.303/32} × log4 ] × log2

= 32 log2/log4

= 32log2/2log2

= 16 min

hence, half life of given reaction is 16 minutes .