The radioactive isotope 32p decays by first-order kinetics and has a half-life of 14.3 days. how long does it take for 75.0% of a sample of 32p to decay?

Answer : The time passed in days is 28.6 days.

Explanation :

Half-life = 14.3 days

First we have to calculate the rate constant, we use the formula :

Now we have to calculate the time passed.

Expression for rate law for first order kinetics is given by:

where,

k = rate constant  =

t = time passed by the sample  = ?

a = let initial amount of the reactant  = 100 g

a - x = amount left after decay process = 100 - 75.0 = 25.0 g

Now put all the given values in above equation, we get

Therefore, the time passed in days is 28.6 days.

c

explanation: