Chapter 3.7, Problem 1PPA

Interpretation Introduction

Interpretation:

The number of oxygen atoms, oxygen molecules, presentin the given sample, and the mass of the given number of ${\text{SO}}_3$ molecules are to be calculated.

Concept introduction:

Stoichiometry involves calculations of number of atoms of reactants and products in a balanced chemical equation.

Number of moles of a compound is the ratio of given mass and the molar mass.

The number of molecules can be calculated as

$\begin{array}{l}\text{number}\text{of}\text{molecules}\text{=}\text{number}\text{of}\text{moles×6}{\text{.022×10}}^{\text{23}}\\ \text{=}\frac{\text{given}\text{mass}}{\text{molar}\text{mass}}\text{×6}{\text{.022×10}}^{\text{23}}\end{array}$

The mass of a compound can be calculated as

$\text{Mass}\text{of}\text{compound}=\frac{\text{number}\text{of}\text{molecules}\times \text{molar}\text{mass}}{\text{6}{\text{.022×10}}^{\text{23}}}$