Question

The half-life of element X is 20 years. If there are 48 g initially a) How much is there after 80 years

Answer 1

After 80 years there will be 3 g of element X remaining

Step-by-step explanation:

Given;

the half life of element X = 20 year

initial mass of element X = 48 g

a) How much is there after 80 years

0 year --------------------------> 48 g

20 years -----------------------> (48g / 2) = 24 g

40 years ------------------------> 12 g

60 years ------------------------> 6 g

80 years --------------------------> 3 g

Therefore, after 80 years there will be 3 g of element X remaining.