## Gram Formula Mass :

Gram formula mass_{( g) }in grams is equal to the product of mass of the solute _{( g) }in grams and division of the formula mass of the solute _{( g) } in grams Hence gram formula can be written as

The Gram formula mass as the standard unit of measure in grams

Gram formula Mass_{(g)}= mass of the solute_{(g)} / formula mass of the solute_{(g)}

## Sample Problems :

### Example 1

Calculate the gram formula mass of 1 mol of KAI( SO_{4})_{2}.12H_{2 }0?

### Solution :

1 K=39

1AI=27

2( SO_{4})=192=2(32+16 ×4)

12H_{2 }0 =216=12(2+16)

Therefore the gram formula mass is

Gram formula Mass(grams)= mass of the solute(grams) / formula mass of the solute(grams)

1mol=474g

### Example 2 :

Calculate the gram formula mass of 1 mole of caco_{3}?

### Solution :

1 ca =40

1 c=12

30=48=3×16

Therefore the gram formula mass of caco_{3} is

caco_{3}=100 formula mass

caco_{3}=100g =gram formula weight.