Question

50 litres of water containing ca(hco3)2 when converted into soft water required 22.2 gram of ca(oH)2 calculate the amount of ca(hco3)2 per litre of hard water...plzhelp​

Answer 1

Answer:

The amount of Ca(HCO_3)_2Ca(HCO3)2

present in per litre of hard water is 0.972

Explanation:

The reaction is

Ca(HCO_3)_2+Ca(OH)_2\rightarrow2CaCO_3+2H_2OCa(HCO3)2

+Ca(OH)2

→2CaCO

3

+2H

2

O

Molecular weight of Ca(HCO_3)_2Ca(HCO

3

is 162

Molecular weight of Ca(OH)_2Ca(OH)

2

is 74

Thus,

74 gram (1 mole) of Ca(OH)_2Ca(OH)2

reacts with 162 gram of Ca(HCO_3)_2Ca(HCO3)2

Thus, 1 gram of Ca(OH)_2Ca(OH)2

reacts with = \frac{162}{74}

74

162

gram of Ca(HCO_3)_2Ca(HCO

3)2

22.2 gram of of Ca(OH)_2Ca(OH)

2

reacts with = \frac{162}{74}\times 22.2=48.6

74

162

×22.2=48.6 gram of Ca(HCO_3)_2Ca(HCO3)2

Thus,'

50 litres of water contains 48.6 gram of Ca(HCO_3)_2Ca(HCO3)2

1 litre of water will contain =\frac{48.6}{50}=0.972=

50

48.6

=0.972 gram of Ca(HCO_3)_2Ca(HCO3)2