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# Molar Mass Formula

When a formula mass of an ionic compound is determined by the addition of its component relative atomic masses and expressed in grams it is called the molar mass.

The mass of one mole of an element or compound is called it molar mass (symbol M). There is a quantity that relates to the number of particles in a mass of substance.

Molar Mass Formula is expressed as

The molar mass is the sum of atomic masses and it must be known to determine a molecular formula from the empirical formula.

 Related Calculators Calculating Molar Mass of a Gas Chemistry Molar Mass Calculator formula mass calculator Calculate Molarity

## Molar Mass Problems

Solved problems based on molar masses are given below.

### Solved Examples

Question 1: Find the molar mass of CaCO3.
Solution:

1 Ca = 40
1 C = 12
3 O = 48 = (3 $\times$ 16)

CaCO3 = 100 formula mass
= 100 g/mol is the molar mass

The molar mass is equivalent to the mass of 1 mole of that compound expressed in grams.

Question 2: Find the molar mass of 1 mole of KAl(SO4)2.12H2O.
Solution:

1K = 39
1 Al = 27
2 (SO4) = 192 = 2(32+16$\times$4)
12 H2O = 216 = 12(2+16)

1 mole = 474g

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