Acids, bases and salts Worksheet-7

Acids, bases and salt Worksheet-7

Multiple Choice Questions (with more than one option):

1. Life cannot exist on Venus because

(A) It has a reducing atmosphere

(B) It has 97% carbon –di-oxide.

(C) It’s atmosphere is made of thick white and yellowish clouds of sulphuric acid

(D) It’s atmosphere  has argon, helium neon and krypton

(E) The temperature of Venus is very less

2. What are the compounds formed when lime stone (CaCO₃) reacts with Dil sulphuric acid (H₂SO₄)?

(A) CaSO_­4, H_2(g) + H₂O_(i)                   (B) CaS, CO_2(g), H₂O_(l)

(C) CaSO₄, CO_2(g), H₂O_(g)                  (D) CO_2(g), H₂O_(l)

3. What is the role of hydrochloric acid in stomach?

(A) It provides acidic medium for the activity of pepsin

(B) It kills microorganisms which may get entry to stomach

(C) It breaks peptide bonds.

(D) It aids in digestion of lipids.

(E) Acidic medium is also required for digestion of carbohydrates.

4. Identify the salt whose aqueous solution has pH more than 7.

(A) NaCl                         (B) Na₂SO₄                    (C) CH₃COONa

(D) K₂CO₃                      (E) (NH₄)₂SO₄

5. Process of adding conc. Acid to water is

(A) Endothermic

(B) Exothermic

(C) Temperature of container increases

(D) Temperature of container decreases

(E) No change in temperature

6. A white crystalline solid (A) when treated with dil Hydrochloric acid evolves a gas which turns lime water milky. What is A.

(A) It  is also used as antacid          (B) Na₂CO₃

(C) It is used for washing                (D) Na₂O

(E) NaHCO₃

7. Why acids are good conductors of electricity where as glucose and alcohols are not ?

(A) Glucose and alcohols do not contain Hydrogen.

(B) On dissolving in water glucose and alcohols do not produce hydrogen ions in water.

(C) Glucose and alcohols are covalent compounds so they do not form ions.

(D) Ions are carriers of electricity

(E) None of these

8. Sodium hydrogen carbonate and sodium carbonate are bases as-

(A) They neutralize acids

(B) NaHCO₃ is a weak acid also.

(C) They are not a base as they do not furnish OH^– ions in solution.

(D) Their solution in water is alkaline.

Answer key:

1. (B,C)
2. (C,D)
3. (A,B)
4. (C,D)

CH₃COONa and K₂CO₃ are the salts of weak acid and strong base.

       Strong base NaOH and KOH

5. (B,C)
6. (A,E)

NaHCO₃ + HCl → NaCl + H₂O +CO₂

7. (B,C,D)

Glucose and alcohols are covalent compounds so they are poor conductors of electricity.

8. (A,D)