   Chapter 25, Problem 45PS

Chapter
Section
Textbook Problem

Radon has been the focus of much attention recently because it is often found in homes. Radon-222 emits α particles and has a half-life of 3.82 days.(a) Write a balanced equation to show this process.(b) How long does it take for a sample of 222Rn to decrease to 20.0% of its original activity?

(a)

Interpretation Introduction

Interpretation:

Equation for decomposition of Radon-222 has to be written.

Concept introduction:

Balancing nuclear reaction equation: The balanced nuclear reaction should conserve both mass number and atomic number.

• The sum of the mass numbers of the reactants should be equal to the sum of mass numbers of the products in the reaction.
• The sum of atomic numbers (or the atomic charge) of the reactants should be equal to the sum of atomic numbers (or the atomic charge) of the products in the reaction.
Explanation

The decomposition of Radon-222 to polonium-218 by the emission of alpha particle, the balanced equation is written as follows,

R86222nP

(b)

Interpretation Introduction

Interpretation:

The time required for sample of Radon-222 decrease to 20% of its original activity has to be calculated.

Concept Introduction:

Radiocarbon dating: The dynamic equilibrium exists in all living organism by exhaling or inhaling, maintain the same ratio of 12C and 14C that takes in. when the living organism dies, the intake of 14C stops and it’s the ratio no longer exhibits equilibrium; undergoes radioactive decay.

Half-life period: The time required to reduce to half of its initial value.

Formula used to calculate half-life:

t1/2=0.693kwhere,kis rate constant.(or)ln[N]t- ln[N]0= -kt

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Find more solutions based on key concepts 