Acids, bases and salts Worksheet-3

Acids, bases and salts Worksheet-3

 

Multiple Choice Questions:

  1. Distilled water does not conduct the electricity whereas rain water does.

(A) Distilled water is germ free water

(B) Distilled water contains mineral ions.

(C) Rain water contains ions.

(D) Rain water contain microorganisms.

 

  1. What is the colour of methyl orange in baking soda solution?

(A) Red                 (B) Yellow            (C) Orange

(D) Pink               (E) colourless

 

  1. Why does CO2 gas turn limewater milky?

(A) CO2 reacts with Ca(OH)2 forming calcium carbonate

(B) CO2 reacts with Ca(OH)2 forming calcium carbonate

(C) CO2 reacts with water forming calcium hydroxide

(D) None of these

 

  1. Dry litmus paper does not show colour change with dry HCl why?

(A) The dye present in the litmus doesn’t react with dry HCl

(B) Protons formed during ionization of acid change the colour of litmus paper

(C) Chloride ions are required for changing the colour of litmus paper

(D) Hydroxide ions formed during ionization of water reacts with the dye and changes its colour

 

  1. Which acid is present in fatigued muscles ?

(A) Citric acid                                   (B) Hydrochloric acid  

(C) Lactic acid                                   (D) Acetic acid

 

  1. How is the concentration of hydronium ion  H3O+ affected when a solution of an acid is diluted?

(A) It will increase                           (B) It will decrease

(C) It will remain the same             (D) Cannot be predicted

 

  1. For diluting a mineral acid

(A) Concentrated acid is added to water with stirring

(B) water is added to concentrated acid with stirring

(C) Both acid and water are added simultaneously in a beaker

(D) water and acid should not be mixed

 

  1. What are the products of given reaction. Fe + 2HCl(dil or Conc.)

(A) FeCl2 + H2O                                 (B) FeCl3 + H2

(C) FeCl2 + H2(g)                                (D) FeCl2

 

  1. What will be the products formed when egg shell is treated with dil. Sulphuric acid?

(A) CaSO4 + CO2 + H2O

(B) CaSO4 + CO + H2

(C) CaSO4 + CO2

 

  1. Which of the following is the strongest base ?

(A) Al(OH)3          (B) Ca(OH)2          (C) Mg(OH)2        (D) Be(OH)2

 

Answer Key:

  1. (C)

Distilled water does not contain ions where as rain water contains mineral ions which carry electric current.

  1. (B)

Baking soda contains sodium hydrogen carbonate, which gives alkaline solution in water.

  1. (A)

due to the formation of calcium carbonate lime water turns milky.

  1. (B)
  2. (C)
  3. (B)

When a solution is diluted    number of moles of H3O+ per ml decreases.

  1. (A)

When concentrated acid is added to water then heat is evolved gradually and is easily absorbed by large amount of water.

When water is added to concentrated acid then large amount of heat is evolved at once and it catches fire.

  1. (C)
  2. (A)

CaCO3 + H2SO4 → CaSO4 + H2O + CO2 Egg shell is made of calcium carbonate.

  1. (B)