Question

Phosphorus reacts with chlorine gas to produce phosphorus trichloride:

1. Write the chemical equation and balance
2. How many moles of chlorine gas are required to produce 17 moles of PCI3 ?

Answer 1

1. P4 + 6Cl2 → 4PCI3; already balanced

2. 25.5 moles Cl2

Step-by-step explanation:

1. The chemical equation for the reaction of phosphorus with chlorine gas to produce phosphorus trichloride is:

P4 + 6Cl2 → 4PCI3

The equation is already balanced

2. The equation shows that 6 moles of chlorine gas are required to produce 4 moles of phosphorus trichloride.

set up a proportion:

6 moles Cl2 / 4 moles PCI3 = x moles Cl2 / 17 moles PCI3

solve for x:

x = (6 moles Cl2 / 4 moles PCI3) x 17 moles PCI3

x = 25.5 moles Cl2

Therefore, 25.5 moles of chlorine gas are required to produce 17 moles of phosphorus trichloride.

Answer 2

25.5 moles of Cl₂ required

Step-by-step explanation:

2P + 3Cl₂ --> 2PCl₃

Since, the stoichiometry (molar ratio) of the reaction is 2 : 3 : 2,

thus, number of moles of Cl₂ = 3/2 × number of moles of PCl₃

∴ number of moles of Cl₂ required is 25.5 moles