51. Which of the following is the most electronegative element?

A) Oxygen
B) Chlorine
C) Fluorine
D) Bromine
Answer: C) Fluorine

52. Which type of bond is formed between metal atoms?

A) Ionic
B) Covalent
C) Metallic
D) Hydrogen
Answer: C) Metallic

53. What is the main component of limestone?

A) Calcium Carbonate
B) Calcium Oxide
C) Magnesium Carbonate
D) Silica
Answer: A) Calcium Carbonate

54. Which element has the highest atomic mass?

A) Lead
B) Uranium
C) Gold
D) Mercury
Answer: B) Uranium

55. What is the primary use of the element Uranium?

A) Making batteries
B) Producing electricity
C) Manufacturing steel
D) Producing glass
Answer: B) Producing electricity

56. Which of the following is an example of an acidic oxide?

A) CO2
B) Na2O
C) CaO
D) MgO
Answer: A) CO2

57. What is the electron configuration of Oxygen?

A) 1s2 2s2 2p4
B) 1s2 2s2 2p6
C) 1s2 2s1
D) 1s2 2s2 2p5
Answer: A) 1s2 2s2 2p4

58. Which of the following elements is a transition metal?

A) Sodium
B) Iron
C) Calcium
D) Carbon
Answer: B) Iron

59. Which gas is used to inflate balloons?

A) Oxygen
B) Carbon Dioxide
C) Helium
D) Hydrogen
Answer: C) Helium

60. Which of the following is a reducing agent?

A) Oxygen
B) Chlorine
C) Hydrogen
D) Nitrogen
Answer: C) Hydrogen