If a sample of C-14 initially contains 1.6 mmol of C-14, how many millimoles will be left after 2250 years

1.2 millimoles will be left after 2250 years

Explanation:

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

where,

k = rate constant

t = age of sample

a = let initial amount of the reactant

a - x = amount left after decay process  

a) for completion of half life:

Half life is the amount of time taken by a radioactive material to decay to half of its original value.

b) Amount left after 2250 years

Thus 1.2 millimoles will be left after 2250 years