7.15 MHCERT 7th General Science 15.Matarials We Use
MHCERT General Science 7th Materials We Use 1. Fill appropriate terms in the blanks. (white cement, soap, detergent, wearing of bones, tooth decay, hard, soft, Portland, fatty acid) 3. 4. Pro (a) The substance that helps water to remove dirt from the surface of materials is called (b) Fluoride is used in toothpaste to prevent (c) Soap is a salt of sodium hydroxide. and (d) Synthetic detergents can be used in water as well. (e) For construction purposes cement is the most commonly used cement. 2. Write answers questions. to the following (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 cement? (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 i...