“Periodic Table” MCQ with Answer Explanation.

91. Which of the following statements is true about metalloids?
    A) They are excellent conductors of electricity.
    B) They are malleable like metals.
    C) They have properties of both metals and nonmetals.
    D) They are highly reactive with water.
    Answer: C) They have properties of both metals and nonmetals.

Explanation: Metalloids have characteristics that are intermediate between metals and nonmetals. They can exhibit both metallic and non-metallic behaviors.

92. Which of the following elements is likely to form an ionic compound with chlorine?
    A) Sulfur
    B) Phosphorus
    C) Magnesium
    D) Argon
    Answer: C) Magnesium

Explanation: Magnesium (Mg) is a metal and tends to lose two electrons to form Mg²⁺ ions, which can combine with Cl⁻ ions to form the ionic compound MgCl₂.

93. Which of the following elements is found in the d-block of the periodic table?
    A) Oxygen
    B) Copper
    C) Neon
    D) Calcium
    Answer: B) Copper

Explanation: Copper (Cu) is a transition metal found in the d-block of the periodic table. It has variable oxidation states and is known for its good electrical conductivity.

94. Which of the following elements is a noble gas?
    A) Hydrogen
    B) Helium
    C) Nitrogen
    D) Oxygen
    Answer: B) Helium

Explanation: Helium (He) is a noble gas with a complete outer electron shell. It is inert and does not easily form compounds.

95. Which element has the highest first ionization energy in Group 15?
    A) Nitrogen
    B) Phosphorus
    C) Arsenic
    D) Antimony
    Answer: A) Nitrogen

Explanation: Nitrogen (N) has the highest first ionization energy among Group 15 elements due to its small atomic size and strong nuclear attraction for its valence electrons.

96. Which of the following elements is a member of the actinide series?
    A) Lanthanum
    B) Uranium
    C) Hafnium
    D) Yttrium
    Answer: B) Uranium

Explanation: Uranium (U) belongs to the actinide series, which includes elements with atomic numbers 89 to 103. These elements are located in the f-block of the periodic table and are radioactive.

97. Which of the following elements is most likely to form covalent bonds?
    A) Sodium
    B) Magnesium
    C) Carbon
    D) Potassium
    Answer: C) Carbon

Explanation: Carbon (C) commonly forms covalent bonds by sharing electrons with other atoms. It has four valence electrons and can form multiple covalent bonds.

98. Which element is located in Group 14 and Period 3?
    A) Silicon
    B) Carbon
    C) Germanium
    D) Tin
    Answer: A) Silicon
99. Which element in the periodic table has the highest electronegativity?
    A) Fluorine
    B) Oxygen
    C) Chlorine
    D) Nitrogen
    Answer: A) Fluorine
100. Which of the following elements has the smallest atomic radius?
     A) Potassium
     B) Sodium
     C) Chlorine
     D) Bromine
     Answer: C) Chlorine
101. Which element is a member of the alkali metals?
     A) Calcium
     B) Sodium
     C) Magnesium
     D) Aluminum
     Answer: B) Sodium
102. Which element has the electronic configuration [Ne] 3s² 3p¹?
     A) Magnesium
     B) Aluminum
     C) Silicon
     D) Phosphorus
     Answer: B) Aluminum