Unit 2: S-Block Elements

51. The reactivity of which alkali metal with water is the most vigorous?

a) Lithium
b) Sodium
c) Potassium
d) Rubidium
Answer: c) Potassium

52. Which s-block element is used in fireworks to produce a bright red flame?

a) Calcium
b) Strontium
c) Magnesium
d) Barium
Answer: b) Strontium

53. The solubility of alkaline earth metal oxides in water:

a) Decreases down the group
b) Increases down the group
c) Remains constant
d) Increases up the group
Answer: b) Increases down the group

54. The s-block metal with the highest melting point is:

a) Lithium
b) Sodium
c) Magnesium
d) Potassium
Answer: a) Lithium

55. The compound formed when an alkali metal reacts with oxygen is generally:

a) A peroxide
b) A superoxide
c) An oxide
d) A carbonate
Answer: a) A peroxide

56. The s-block metal used in the production of various alloys is:

a) Calcium
b) Magnesium
c) Sodium
d) Potassium
Answer: b) Magnesium

57. Which s-block metal reacts with nitrogen to form a nitride?

a) Sodium
b) Magnesium
c) Potassium
d) Calcium
Answer: c) Potassium

58. The s-block element that is used in toothpaste for its abrasive qualities is:

a) Sodium
b) Calcium
c) Potassium
d) Magnesium
Answer: b) Calcium

59. The most common application of sodium bicarbonate is as:

a) A disinfectant
b) A leavening agent
c) A fertilizer
d) A bleach
Answer: b) A leavening agent

60. Which s-block element forms a basic hydroxide that is used in cleaning products?

a) Sodium
b) Potassium
c) Calcium
d) Magnesium
Answer: a) Sodium