Chapter 18, Problem 31QAP

Interpretation Introduction

Interpretation:

The number of counts should be determined.

Concept introduction:

Activity is defined as the product of rate constant and number of atoms. It is also defined as the rate of decay or expresses number of atoms decays in unit time.

The mathematical expression is given by:

$\text{A = kN}$

Where, A = activity, k = first order rate constant and N = number of radioactive nuclei.

Activity can be expressed in following units:

1 Bq = 1 atom/s

1 Ci = 3.700 × 10¹⁰ atoms/s

The relation between half-life and first order rate constant is given by:

$\text{k=}\frac{\text{0}\text{.693}}{{\text{t}}_{\text{1/2}}}$

Where, k = first order rate constant and ${\text{t}}_{\text{1/2}}$ = half-life