Question

The decay constant of radium is 4.28 × 10⁻⁴ per year. Its half life will be(a) 2000 years(b) 1240 years(c) 63 years(d) 1620 years

Answer 1

$<b>$

Option A is Correct

Answer 2

The decay constant and the half time of the radioactive materials are mathematically related with each other.

The mathematical relationship between then is:

Half time=0.693/decay constant

[According to the data mentioned in the question]

Half time=0.693/4.28 × 10⁻⁴

Half time = 1619.158

Half time= 1620 [approximately]

That's why the correct answer of this question is option d,1620 years.