A 200 mL sample of water requires 5 " mL of " `(N)/(20)Na_2CO_3` solution for complete precipitation of `Ca^(2+)` and `CaCO_3`. Calculate the hardness in ppm.

A 200 mL sample of water requires 5 " mL of " `(N)/(20)Na_2CO_3` solut

1.	A 200 mL sample of water requires 5 " mL of " `(N)/(20)Na_2CO_3` solution for complete precipitation of `Ca^(2+)` and `CaCO_3`. Calculate the hardness in ppm.
Answer» `5 " mL of " (N)/(20) Na_(2)CO_(3)=(5xx50)/(20xx1000)g CaCO_(3)` So, 200 parts of water contains`=(5xx50)/(20xx1000)` parts of `CaCO_(3)` equivalent `10^(6)` parts of water contains`=(5xx50xx10^(6))/(20xx1000xx200)` `=62.5 ppm` Therefore, hardness`=62.5 ppm`

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A 200 mL sample of water requires 5 " mL of " `(N)/(20)Na_2CO_3` solution for complete precipitation of `Ca^(2+)` and `CaCO_3`. Calculate the hardness in ppm.

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