Question

a first order reaction is 50% complete in 30 min how long it will take to be 10% complete​

Answer 1

Step 1) Using t1/2=0.693/k we will get the value of k

Step two Now using formula t=2.3/k logA°/A we will get t

here t come out to be 4.5min

Answer 2

Explanation:

this is the correct answer