WORKSHEET 2, CH 5(CLASS 7)

1. What is the chemical nature of a compound that turns blue litmus red?
2. Give the names of two weak acids.
3. Why do some fruits taste sour?
4. Where is lactic acid found?
5. Name the acid which is found in our body cells.
6. How can you remove the acidity of soil ?
7. Antacid tablets contain............................. which neutralise the excess acid formed in our body.
8. ............is the reaction between acid and base to form salt and water.
9. Bases are............ to taste and acids are ..........to taste.
10 If china rose indicator is added to acidic solution, it turns............ and when added to basic solution, it turns.............
11. Why is factory waste neutralized before disposing it into the water bodies?
12. Blue litmus paper is dipped in a solution. It remains blue. What is the nature of the solution?
13. What is acid rain ? What are its ill effects ?
14. The acid used for preserving food articles is-
      (A) Acetic acid. (B) Tartaric acid. (C) Sulphuric acid. (D) Nitric acid.
15. ..............is known as ascorbic acid which is present in citrus fruits.
       (A) Vitamin D. (B) Vitamin C. (C) Vitamin A. (D) Vitamin K.
16. When a drop of phenolphthalein is introduced in lime water, the solution turns-
       (A) Blue. (B) Red. (C) Milky. (D) Pink.
17. Acid rain is caused due to ...................
        (A) CO2, O2, SO2 (B) CO2, NO2, H2 (C) SO2 N2, O2 (D) CO2, SO2, NO2
18. The industrial waste is ................... in nature.
       (A) Acidic (B) Basic (C) Neutral (D) Both (a) & (b).
19. Milk of magnesia used to treat acidity in stomach, contains this base.
       (A) Magnesium hydroxide. (B) Ammonium hydroxide. (C) Sodium hydroxide. (D) Copper                  hydroxide.
20. In this reaction what are the reactants and the products:
      acid+base----------------salt+water

(5 mark question)
1. Three liquids are given to you. One is hydrochloric acid; another is sodium hydroxide and third is       a sugar solution. How will you indentify them? You have only turmeric indicator.
2. Explain the process of Neutralization. Give an example