Question

The reaction of chlorine gas with solid phosphorus (P4)produces solid phosphorus pentachloride. When 16.0 g chlorine reacts with 23.0 g P4, which reactant limits the amount of phosphorus pentachloride produced? Which reactant is in excess?

Answer 1

Chlorine gas limit the amount of production of phosphorus pentachloride. And phosphorus was in excessive amount

37.49 grams of phosphorus pentachloride was produced.

Step-by-step explanation:

`P_4+10Cl_2\rightarrow 4PCl_5`

Moles of solid phosphorus =
`(23.0 g)/(124 g/mol)=0.1854 mol]`

(Molar mass of
`P_4` = 4 × 31 g/mol =124 g/mol)

Moles of chlorine gas =
`(16 g)/(35.5 g/mol)=0.4507 mol`

According to reaction 1 mole of
`P_4` reacts with 10 mol of chlorine gas.Then 0.1854 moles of
`p_4` will react with 1.854 mol of chlorine gas.

This means that chlorine gas is in limiting amount and
`P_4` is in excessive amount.

The production of phosphorus pentachloride will depend upon the amount of chlorine gas.

According to reaction 10 moles of chloroen gas will produce 4 moles of phosphorus pentachloride.

Then 0.4507 moles of chlorine gas will produce:

`(4)/(10)* 0.4507 mol=0.18028 mol` of phosphorus pentachloride.

Mass of 0.18028 mol of phosphorus pentachloride:

0.18028 mol × 208.5 g/mol=37.49 g

37.49 grams of phosphorus pentachloride was produced.

Answer 2

The balanced chemical equation would be as follows:

P4(s)+10Cl2(g)--4PCl5(g)

We are given the amount of the reactants to be used for the reaction. We need to determine first which one is the limiting reactant. We do as follows:

16.0 g Cl2 ( 1 mol / 70.9 g ) = 0.23 mol Cl2 -----> consumed completely and therefore the limiting reactant
23.0 g P4 ( 1 mol /123.90 g ) = 0.19 mol P4 ------> excess reactant