Question

5. 0.28
gm of CaCO3 was dissolved in HCl and the solution made up to 1000 ml with distilled
water. 100 ml of this solution required 28 ml of EDTA solution for titration. 100 ml of hard water
sample required 33 ml of EDTA and after boiling and filtering required 10 ml of EDTA solution.
Calculate temporary hardness of water.
6.​

Answer 1

Answer:

To calculate the temporary hardness of the water, we need to use the formula:

Temporary hardness = (EDTA titer x volume of EDTA used for sample - EDTA titer x volume of EDTA used after boiling) x 1000/ volume of sample

Here, EDTA titer is the concentration of the EDTA solution, and it is not given in the problem. We will assume it to be 0.01 N.

So, the temporary hardness of the water is:

Temporary hardness = (0.01 x (33 - 10)) x 1000/100

Temporary hardness = 2.3 mg/L

Therefore, the temporary hardness of the water sample is 2.3 mg/L.