Chapter 9, Problem 9.73AP

(a)

Interpretation Introduction

Interpretation:

The balanced equation for the decay of Iridium-192 has to be given.

(b)

Interpretation Introduction

Interpretation:

The amount of Irirdium-192 after five $\text{30}$ days has to be given.

Concept Introduction:

Theradioactive lawstates that the probability per unit time that a nucleus will decay is a constant independent of time. This constant is calledthe decay constant and is denoted by $\text{k}$.  This constant probability may vary greatly between different types of nuclei, leading to the many different observed decay rates. The radioactive decay of certain number of atoms (mass) is exponential in time.

Radioactive decay law,

  ${\text{m= m}}_{\text{0}}{\text{.e}}^{\text{-kt}}$

Where m is the mass of the sample after time t.

m₀ is the mass of the sample in initial time.

k is the decay constant.

t is the time required to decay.

(c)

Interpretation Introduction

Interpretation:

The activity of iridium-192 after ten $\text{30}\text{d}$ has to be given.

Concept Introduction:

Refer to part (b).