Define the degree of hardness, and its use and units

 Degree of hardness, its use and units:

 

Definition:

• The degree of hardness refers to the amount of dissolved minerals, such as calcium and magnesium ions, in a given water supply.

Uses:

• The degree of hardness is an important water quality parameter because it affects the properties of water, such as taste, lathering ability, and the ability to form suds.

Units: 

• The degree of hardness is typically measured in milligrams per liter (mg/L) or parts per million (ppm). 
• Different regions may use different units for measuring hardness, but mg/L and ppm are the most commonly used.