Answer:
a. 2.6 x 102 ms
Explanation:
Initial mass [Ao] = 99 g
Final mass [A] = 0.50 g
Half life (t1/2) = 35 ms
Time ( t ) = ?
]The integrated rate law for first order reactions is given as;
To obtain k, we look at the expression for the half life of a first order reaction;
t1/2 = 0.693 / k
k = 0.693 / 35 = 0.0198 ms-1
ln[A] = ln[Ao] - kt
kt = ln[Ao] - ln[A]
t = ( ln[Ao] - ln[A] ) / k
t = ( ln(99) - ln (0.50) ) / 0.0198
t = 5.288 / 0.0198
t = 267.07 ms
correct option is;
a. 2.6 x 102 ms
