Question

Waters that contain a significant concentration of dissolved minerals like calcium, magnesium, strontium, iron, and manganese, are called "hard“ because

I. Its salts are difficult to separate from them

II. Only give a lather when adding a lot of soap

III. Do not give soap when adding soap to it

IV. Water contains heavy minerals and is not important to the body

Answer 1

Answer:

(4)water contains heavy minerals and is not important to the body