0
You visited us 0 times! Enjoying our articles? Unlock Full Access!
Question

Number of moles of CaO required to remove hardness from 1000 litre water having 324 ppm of calcium bicarbonate.
  1. 8
  2. 4
  3. 3
  4. 2

A
4
B
3
C
2
D
8
Solution
Verified by Toppr

Ca(HCO3)2+CaO2CaCO3+H2O.

Molecular weight of Ca(HCO3)2 =162 gms

Moles of Ca(HCO3)2=324162=2

From the reaction, it is clear that 1 mole of CaO is required for one mole of calcium bicarbonate, thus for 2 moles of calcium bicarbonate, we require 2 moles of CaO.

Was this answer helpful?
0
Similar Questions
Q1
Number of moles of CaO required to remove hardness from 1000 litre water having 324 ppm of calcium bicarbonate.
View Solution
Q2
Calculate the amount of Ca(OH)2 required to remove the hardness in 60 litre of pond water containing 1.62mg of calcium bicarbonate per 100mL of water.
View Solution
Q3
What is the amount of lime Ca(OH)2 required to remove the hardness in 60 litres of pond water containing 1.62 mg of calcium bicarbonate per 100 mL of water?
View Solution
Q4
A sample of hard water contains 96 ppm of SO24 and 183 ppm of HCO3 with Ca2+ as the only cation. Few moles of CaO will be required to remove HCO3 from 1000 kg of this water. If 1000 kg of this water is treated with the amount of CaO calculated above, the concentration (in ppm) of residual Ca2+ ions will be :
(Assume CaCO3 to be completely insoluble in water. The Ca2+ ions in one litre of the treated water are completely exchanged with hydrogen ions. One ppm means one part of the substance in one million part of water, mass/mass)
View Solution
Q5
100 mL of a water sample contains 0.81 g of calcium bicarbonate and 0.73 g of magnesium bicarbonate. The hardness of this water sample expressed in terms of equivalents of CaCO3 is:
(molar mass of calcium bicarbonate is 162 gmol1 and magnesium bicarbonate is 146 gmol1)
View Solution