6 ml of a standard soap solution (1ml = 0.001g of `CaCO_3` ) were required in titrating 50ml of water to produce a good lather. Calculate the degree of hardness.

Explanation

50ml of hard water sample requires 6 ml of soap solution.
Volume of soap solution required requid fort `10^(6)` ml of hard water to get good lather `=(10^(6)xx6)/(50)=0.12xx10^(6)m`
Given that if 1 ml soap is required for the water sample to get lather, that sample contains . 0.001g of `CaCO_(3)`
`1"ml" "soap" to 10^(-3)g CaCO_(3)`
`0.12xx10^(6)"ml" "saop"to?`
Weight equivalent of `CaCO_(3)=120g`,Degree of hardness of water sample = 120ppm