Exercise: Acids, Bases and Salts

Multiple Choice Questions

A solution turns red litmus blue. Its pH is likely to be-

An element common in all acids is-

Which acid is present in sting of a honey bee?

Olfactory indicator is-

Dissolution of acid or base in water is-

An indicator is what type of compound?

The organic acid present in tomato is-

HCl acid reacts with NaOH to form salt and water. This reaction is called-

A solution reacts with crushed eggshells to give a gas that turns lime water milky. The solution contains-

Which one of the following types of medicines is used for treating in digestion?

A solution turns blue litmus to red, its pH is likely to be-

Fill in the Blanks

  1. The acid present in lemon is ________.
  2. The first clear expression of nationalism came with the French Revolution in AD ________.
  3. Chemical name of baking soda is ________.
  4. Egg shell is made up of _______.
  5. If the pH of a solution is greater than 7, the solution will be ______.
  6. Mixing of concentrated acid or base with water is a highly ________ reaction.
  7. Tooth enamel corrodes if the pH of mouth is less than _______.
  8. pH of a neutral solution is ______.
  9. Litmus is a ______ indicator.
  10. ________changes blue litmus to red.
  11. _______ acid is present in vineger.
Answers

(1). Citric acid, (2). Calcium sulphate hemihydrate, (3). Sodium hydrogen carbonate (NaHCO₃), (4). Calcium Carbonate, (5). Basic, (6). Exothermic, (7). 5.5, (8). 7, (9). Natural, (10). Acid, (11). Acetic

True/ False

  1. Distilled water does not conduct electricity. (T/ F)
  2. Acidity is cured by analgesic. (T/ F)
  3. pH of a solution can range from 0-14. (T/ F)
  4. HCI is a weak acid. (T/ F)
  5. NaOH is a strong base. (T/ F)
  6. When the pH of rain water becomes less than 5-6, it is called acidic rain. (T/ F)
  7. Reactivity of a solution is determined by its pH value. (T/ F)
  8. Turmeric turns dark brown in colour in basic medium. (T/ F)
Answers

(1). True, (2). False, (3). True, (4). False, (5). True, (6). True, (7). False, (8). True

One-Word Answer

  1. What is the pH value of pure water?
  2. Which acid is produced in our stomach?
  3. Which acid is present in Nettle leaves?
  4. What is the chemical formula of washing soda?
  5. What are the products formed in chlor-alkali process?
  6. What is brine?
  7. What is water of crystallisation?
  8. What is the effect of an acid and a base on the smell of an onion?
  9. Write the pH value of acidic solution.
  10. What is the common name of the compound CaOCl₂?
Answers

(1). 7, (2). HCL, (3). Methanoic acid, (4). Sodium carbonate, Na₂CO₃.10H₂O, (5). Chlorine (chlor), Sodium hydroxide (alkali), and hydrogen, (6). Aqueous solution of sodium chloride, (7). Water of crystallisation is the fixed number of water molecules present in one formula unit of a salt, (8). Smell of an onion remains as such in the presence of an acid and it diminishes or fades away in the presence of a base., (9). Less than seven, (10). Bleaching power.

, (8). Paul Chee, (9). Emmanuel II, (10). On the public squares

Match the column

Section ASection B
1). Vinegar a). Plaster of Paris  
2). Magnesium hydroxide b). Baking soda
3). Moisture-proof container c). Acetic acid
4). Fire extinguisher d). Milk of Magnesia  
5). Sodium carbonate e). HCL
6). Formula of common salt f). Permanent hardness
7). Strong acid g). NaCl
8). Marble h). CaCO₃
9). Orange  i). methanoic acid
10). Ant stingj). Citric acid
Answers

(1). > (c), (2). > (d), (3). > (a), (4). > (b), (5). > (f), (6). > (g), (7). > (e), (8). > (h), (9). > (j), (10). > (i)