Calculate the molar mass of the sulphur and phosphorus molecule.

For sulphur:

Molar mass of S = 32g/mol


Sulphur is made up of 8 sulphur atoms.


Hence, molar mass of sulphur (S8) is:


8 × 32mol/g = 256mol/g


For phosphorus:


Molar mass of P = 31g/mol


Phosphorus molecule is made up of 4 phosphorus atoms.


Hence, molar mass of sulphur (P4) is:


4 × 31mol/g = 124 mol/g


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