Write answer to the following questions.
(a) How does the use of a detergent help to clean soiled clothes ?
(b) How will you check with the help of soap powder whether water is hard ?
(c) What are the important ingredients of a toothpaste , and what is the function of each ?
(d) What are the ingredients of cements ?
(e) What will happen if cement is not used in making concrete ?
(f) Make a list of detergents that you use.
(g) What should be expected from a detergent for delicate garments ?
(h) What is meant by ' surface activity'? Name three chemicals responsible for the surface activity of various detergents.