Chapter 11, Problem 100A

When copper(ll) oxide is heated in the presence Of hydrogen gas, elemental copper and water are produced. What mass of copper can be obtained if 32.0 g of copper(ll) oxide is used?

Interpretation Introduction

Interpretation:

Mass of Copper is to be determined

Concept introduction:

When copper oxide is heated in presence of hydrogen gas, it produce elemental copper and water.

Answer to Problem 100A

Mass of Copper is 25.54 g

Explanation of Solution

Step 1: write balance chemical equation

$\begin{array}{l}CuO(s)+H2(g)\to Cu(s)+H2O(l)\\ 32g?\end{array}$

Step 2: convert mass of reactant to moles

$\begin{array}{c}MolarmassofCuO=79.53g/mole\\ Moles=\frac{Mass}{Molarmass}\\ MolesofCuO=\frac{32}{79.53}=0.402moles\end{array}$

Step 3: Convert moles of reactant to moles of product using mole ratio

1 mole of CuO produce = 1 moles of Cu

0.402 moles of CuO produce = 0.402 moles of Cu

Step 4: Convert moles of product to mass (theoretical yield)

$\begin{array}{c}Molar\text{}massofCu=63.54g/mole\\ Mass=Molarmass\times Moles\\ MassofCu(Theoreticalyield)=63.54\times 0.402=25.54g\end{array}$