Question

How many moles of Cl2 are needed to to produce 250.g of PCl5 ?

Answer 1

The number of moles of $Cl_2$ required to produce 250 grams of $PCl_5$ would be 3 moles.

Stoichiometric problem

Phosphorus and chlorine react to form phosphorus pentachloride according to the following balanced equation:

$2P + 5Cl_2 -- > 2PCl_5$

From the equation of the reaction, the mole ratio of chlorine and phosphorus pentachloride is 5:2. Thus, 5 moles of chlorine will produce 2 moles of phosphorus pentachloride.

Recall that: mole = mass/molar mass

The molar mass of $PCl_5$ is 208.24 g/mol

Thus, 250 g of $PCl_5$ would be equivalent to:

mole = 250/208.24

         = 1.20 mol

2 mol $PCl_5$ = 5 moles $Cl_2$

1.20 mol = 5 x 1.2/2

              = 3 moles

In other words, 250 g $PCl_5$ will require 3 moles of $Cl_2$.

More on stoichiometric problems can be found here: brainly.com/question/15047541

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