Question

How do you calculate molar mass? For example, what is the molar mass of Cu(NH_{4})_{4}SO_{4}

Answer 1

Hint The molar mass of a given chemical compound or element can be given by dividing the mass of a given chemical compound or element divided by the amount of a substance in moles.

Complete step by step answer:
- Molar mass of a chemical compound or element can be defined as the weight of one mole of a chemical compound or element.
- We obtain the molar mass of a compound by using the atomic masses of all atoms in the molecule.
- It is calculated by adding the individual atomic masses of all the elements present in the compound.
-In case of multiple atoms of the same element in a compound, multiply the number of atoms with the atomic mass of the element and then add with the atomic masses of other elements.
- For the given compound, we have to multiply the atomic mass of the element with the number of atoms of the element present in the compound. We have to follow the same procedure for each element. Then, adding these masses will provide us with the molar mass.
Molar mass of Cu(NH_{4})_{4}SO_{4} = atomic mass of Cu + (4 x atomic mass of N) + (4 x 4 x atomic mass of H) + atomic mass of S + (4 x atomic mass of O)
Molar mass of Cu(NH_{4})_{4}SO_{4} = 63.55 + (4 x 14.01) + (16 x 1.007) + 32.06 + (4 x 16)
Molar mass of Cu(NH_{4})_{4}SO_{4} = 250 grams

- Therefore, the molar mass of Cu(NH_{4})_{4}SO_{4} is 250 grams.

Note: The molar mass can be calculated in many different ways depending upon the data given in the question. For example, molar mass can be calculated by dividing the given mass of substance with the number moles of the substance. While calculating molar mass, be careful to multiply the number of atoms of elements with its atomic mass.