Q: 35 (NDA-I/2011)


Which of the statements given below is/ are correct ? Permanent hardness of water is due to the presence of soluble :
1. chloride of calcium.
2. bicarbonate of calcium.
3. sulphate of magnesium.
4. bicarbonate of magnesium.
Select the correct answer using the code given below :
question_subject: 
Science
stats: 
0,368,824,40,648,256,248