0.50 g of CaCO3 was dissolved in HCl and diluted to 500 ml. 100ml of this solution required 20 ml of EDTA solution for titration. 100 ml of hard water sample required 30 ml of the same EDTA solution for titration. On boiling, titration of 100ml of same water sample required 10 ml of EDTA. Calculate total, temporary and permanent hardness of water. 5M (1 ml of 0.01M EDTA= 1mg of CaCO3)

Step 1: Calculate the amount of CaCO3 in the EDTA solution

Given that 0.50 g of CaCO3 was dissolved in HCl and diluted to 500 ml, and 100 ml of this solution required 20 ml of EDTA solution for titration, we can calculate the amount of CaCO3 in the EDTA solution.

0.50 g of CaCO3 in 500 ml solution Therefore, in 100 ml solution, the amount of CaCO3 = (0.50 g/500 ml) * 100 ml = 0.10 g

Since 20 ml of EDTA solution is required to titrate 100 ml of the solution, the amount of CaCO3 in 20 ml of EDTA solution = 0.10 g

Step 2: Calculate the total hardness of water

Given that 100 ml of hard water sample required 30 ml of the same EDTA solution for titration, the amount of CaCO3 in 30 ml of EDTA solution = (0.10 g/20 ml) * 30 ml = 0.15 g

Therefore, the total hardness of water = 0.15 g/100 ml = 1500 mg/l

Step 3: Calculate the temporary hardness of water

Given that on boiling, titration of 100 ml of same water sample required 10 ml of EDTA, the amount of CaCO3 in 10 ml of EDTA solution = (0.10 g/20 ml) * 10 ml = 0.05 g

Therefore, the temporary hardness of water = 0.05 g/100 ml = 500 mg/l

Step 4: Calculate the permanent hardness of water

The permanent hardness of water = Total hardness - Temporary hardness = 1500 mg/l - 500 mg/l = 1000 mg/l

So, the total hardness of the water is 1500 mg/l, the temporary hardness is 500 mg/l, and the permanent hardness is 1000 mg/l.