50 ml of water has degree of hardness 160ppm. If a standard soap solution is labelled as 1ml = 1mg of `CaCO_3` , what volume of soap solution can produce lather?

A hard water sample contains magnesium bicarbonate only. 100 ml of the hard water sample requires 10 ml. of standard soap solution (1 ml soap solution = 1 mg CaCO_3 ) to get good lather. Find out of the weight of Ca(OH_2) to be added to 10 Kg water sample to make it soft water.

Degree of hardness of a water sample is 100ppm. 50 ml of standard soap solution is added to one kilogram of hard water sample. Calculate the degree of hardness of the resulting water sample. (one ml of soap solution is 0.001 g CaCO_3 ).

50 ml of water sample requires 6 ml of soap solution to produce a good lather. 1 ml of soap solution is equal to 0.001 g of CaCO_3 . Then the degree of hardness of water is

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.

10.6 g Na_2CO_3 are dissolved in water to give 2 M solution. What is the volume of the solution in ml?

The density of 3M solution of NaCL is 1.25 g mL^(-1) . Calculate molality of the solution.

3.645g of HCl are dissolved in water to give 1M solution. What is the volume of the solution in ml?