Question

1. Sodium-24 has a half-life of 15 hours. How much sodium-24 will remain in an

26.0 g sample after 60 hours?

Answer 1

1.625g

Step-by-step explanation:

The half - life of a radioactive substance is the time taken for half of it to decay to half of its original composition.

For the given specie, the original composition is 26g and the half life is 15hrs:

At time 0hrs Mass = 26g

For the first half life at time 15hrs Mass = 13g

30hrs Mass = 6.5g

45hrs Mass = 3.25g

60hrs Mass = 1.625g