Answer to Question #87335 in General Chemistry for solo

Question

1) phosphorus pentachloride is produced by the reaction between phosphine and chlorine gas. What mass of chlorine gas would be required to produce 0.015kg of phosphorus pentachloride

Answer 1

The balanced equation for considered reaction can be written as follows

$PH_3 (g) + 4 Cl_2 (g) \rightarrow PCl_5 (g) + 3 HCl (l)$

$\frac{m(Cl_2)}{M(Cl_2) \cdot n(Cl_2)} = \frac{m(PCl_5)}{M(PCl_5) \cdot n(PCl_5)}$

$m(Cl_2) = \frac{m(PCl_5) \cdot M(Cl_2) \cdot n(Cl_2)}{M(PCl_5) \cdot n(PCl_5)}$

$M(Cl_2) = 2 \cdot 35.453 = 70.906 \; g/mol$

$M(PCl_5) = 1 \cdot 30.974 + 5 \cdot 35.453 = 208.239 \; g/mol$

$m(Cl_2) = \frac{0.015 \cdot 70.906 \cdot 4}{208.239 \cdot 1} \approx 0.0204 \; kg = 20.4 \; g$

Answer: 20.4 g.