Question

what do you mean by the term " Hardness of water is 15 ppm" ?​

Answer 1

Answer:

Parts per million (ppm) is usually defined as 1 mg/L CaCO3 (the definition used below). It is equivalent to mg/L without chemical compound specified, and to American degree. Grains per Gallon (gpg) is defined as 1 grain (64.8 mg) of calcium carbonate per U.S. gallon (3.79 litres), or 17.118 ppm.

Hope it helps you from my side

Answer 2

Answer:

The following classifications are used to measure hardness in water:

soft 0 - 17.1 parts per million (ppm);

slightly hard 17.1 – 60 ppm;

moderately hard 60 - 120 ppm;

hard 120 - 180 ppm;

very hard 180 or more ppm.

Explanation:

Parts per million (ppm) is usually defined as 1 mg/L CaCO3 (the definition used below). It is equivalent to mg/L without chemical compound specified, and to American degree. Grains per Gallon (gpg) is defined as 1 grain (64.8 mg) of calcium carbonate per U.S. gallon (3.79 litres), or 17.118 ppm.

Hope It Helps

BRAINLIEST PLEASE