Chapter 4.5, Problem 4.42QAP

Interpretation Introduction

Interpretation:

To calculate the atomic mass of rubidium using weighted mass method.

Concept introduction:

Atoms of same element having same atomic number, but different mass number are called isotopes. They contain equal number of electrons and protons, but the number of neutrons is different in their nuclei. The atomic mass of such atom is the average mass of all isotopes.

Given:

Mass of ${\text{Rb}}^{\text{85}}=\text{ 84}.\text{91 amu}$ and percentage amount = 72.17 %

Mass of ${\text{Rb}}^{\text{87}}=\text{ 86}.\text{91 amu}$ and percentage amount = 27.83 %