Question

Gram Molecular weight of copper sulphate is:
(A). 160g
(B). 148g
(C). 163g
(D). 152g

Answer 1

- Hint: It is equal to the sum of individual atomic masses of all the atoms present in that molecule. Copper sulfate is also known as blue vitriol.

Complete step-by-step solution -
We know that, elementary entity in case of a molecular substance is the molecule. Hence, molar mass of such a substance would be the mass of its $6.022\text{x1}{{\text{0}}^{23}}$ molecules, which can be obtained from its relative molecular mass or by multiplying the molar mass of each element by the number of its moles present in one mole of the substance and then adding them.
Now, Let us calculate the gram molecular weight of Copper Sulfate,$\text{CuS}{{\text{O}}_{4}}$ is,
Gram molecular Weight of $\text{CuS}{{\text{O}}_{4}}$ = (2x atomic mass of Cu) + (atomic mass of S) + 4x (atomic mass of O)
= (2x 63.546u)+(32u)+(4x16u)
=160u
Also, It should be noted that the unit of g or u is always given before any measurable quantity.
Therefore, the correct option is (a). 160g
Note: For substances which are not molecular in nature, we talk of formula mass. For example, sodium chloride, NaCL is an ionic substance. For this, we write formula mass which is calculated similar to molecular mass. In case of NaCl ,formula mass= mass of 1 Na atom + mass of 1 Cl atom = 23u+35.5u=58.5u