Question

The molecular mass of the compound is 137.32 g/mol. what is the molecular formula of the compound? pcl2 pcl3

Answer 1

the answer to this question is pcl3

Answer 2

Answer: The molecular formula of the compound is $PCl_3$

Explanation:

Molecular mass of the compound is defined as the sum of the masses of all the individual atoms present in a compound.

We are given a molecular mass of 137.32 g/mol and we need to find the molecular formula for this molecular mass. For that we calculate the molecular mass of the given compounds individually and then match the given molecular mass.

Molar mass of phosphorous = 30.974 g/mol

Molar mass of chlorine = 35.453 g/mol

• Molecular mass of $PCl_2=[30.974+(2\times 35.453)g/mol=101.88g/mol$

• Molecular mass of $PCl_3=[30.974+(3\times 35.453)g/mol=137.33g/mol$

As, the molecular mass of  $PCl_3$ matches the given molecular mass.

Hence, the molecular formula of the compound is $PCl_3$