Question

how many moles of pcl₅ can be produced from 59.0 g of cl₂ (and excess p₄)? express your answer to three significant figures and include the appropriate units. view available hint(s)

Explanation:

Step1: Balance reaction equation

Balanced equation: $\text{P}_4 + 10\text{Cl}_2
ightarrow 4\text{PCl}_5$

Step2: Calculate moles of $\text{Cl}_2$

Molar mass of $\text{Cl}_2$ = $70.90\ \text{g/mol}$.
Moles of $\text{Cl}_2 = \frac{59.0\ \text{g}}{70.90\ \text{g/mol}} \approx 0.83216\ \text{mol}$

Step3: Relate moles to $\text{PCl}_5$

Mole ratio $\text{Cl}_2:\text{PCl}_5 = 10:4$.
Moles of $\text{PCl}_5 = 0.83216\ \text{mol} \times \frac{4}{10} = 0.33286\ \text{mol}$

Step4: Round to 3 significant figures

$0.33286\ \text{mol} \approx 0.333\ \text{mol}$

Answer:

0.333 mol