Sodium-24, which is used to locate blood clots in the human circulatory system, has a half-life of 15.0 hours. a sample of sodium-24 with an inital mass of 22.5 g was stored for 60.0 hours. how many grams of sodium-24 is left in the sample after 60.0 hours?

Answer : The amount of sodium-24 is left in the sample after 60.0 hours is, 1.408 grams

Explanation :

Half-life of Sodium-24 = 15.0 hr

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

Now we have to calculate the left amount of Sodium-24.

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

where,

k = rate constant  =

t = age of sample  = 60.0 hr

a = let initial amount of the reactant  = 22.5 g

a - x = amount left after decay process = ?

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

Therefore, the amount of sodium-24 is left in the sample after 60.0 hours is, 1.408 grams