Fill in the blanks :
1. Acids turn ....................... litmus .............. .
2. Bases turn ....................... litmus................
3. Mixture of several indicators is called as ....................... indicator.
4. ....................... helps in determining the hydrogen ion concentration in the solution.
5. In pH scale, 0 is ....................... .
6. In pH scale, 14 is ....................... .
7. In pH scale, 7 indicates ....................... .
8. pH of pure water is ....................... .
9. Tamarind has a ....................... taste.
10. The human body works within the pH range of ....................... .
11. ....................... gas burns with a pop sound making a little explosion.
12. Reactivity of base with non-metallic oxide is an example of ..........reaction.
13. Phenolphthalein indicator turns ....................... in the basic medium.
14. Presence of chlorides and sulphates of Ca, Mg makes water .................. .
*15. Most of the acidic substances are ....................... in taste.
*16. Phenolphthalein is ....................... type of indicator.
*17. The strength of basic substance is represented by ....................... .
*18. pH scale ranges between ....................... to ....................... .
*19. Acid and base react to form ....................... and ....................... .
*20. Sodium or potassium salt of higher fatty acids are ....................... .
*21. In FeSO4, 7H2O, 7H2O represents as ....................... .
*22. 10% NaCl is known as ....................... .
A. Answers.
1. Blue, red
2. Red, blue
3. Universal
4. pH scale
5. most acidic
6. most basic
7. neutral
8. 7
9. Sour
10. 7.35 to 7.45
11. Hydrogen
12. Neutralization
13. Pink
14. Hard
15. Sour
16. Synthetic
17. pOH
18. 0.14
19. Salt, water
20. Soap
21. Water of crystalization
22. Brine
