“Periodic Table” MCQ with Answer Explanation.

Here below some basic MCQ’s about “Periodic Table” with answer which explained in details. Lets check one by one which is given below.

1. The element with the highest ionization energy in the periodic table is:
   A) Helium
   B) Fluorine
   C) Neon
   D) Oxygen
   Answer: A) Helium

Explanation: Ionization energy is the energy required to remove an electron from an atom. Helium has the highest ionization energy because it has a small atomic size and its electrons are very tightly bound to the nucleus, making it difficult to remove an electron.

2. Which of the following elements has the largest atomic radius?
   A) Sodium
   B) Magnesium
   C) Potassium
   D) Calcium
   Answer: C) Potassium

Explanation: Atomic radius increases down a group due to the addition of new electron shells. Among the given options, Potassium (K) is located further down in Group 1, hence it has a larger atomic radius compared to the others.

3. Which of the following elements has the most metallic character?
   A) Fluorine
   B) Oxygen
   C) Sodium
   D) Cesium
   Answer: D) Cesium

Explanation: Metallic character increases as you move down a group and decreases across a period from left to right. Cesium (Cs), being in Group 1 and farthest down, has the most metallic character.

4. Which of the following is the correct order of electron affinity?
   A) F > Cl > Br > I
   B) Cl > F > Br > I
   C) I > Br > Cl > F
   D) Br > Cl > I > F
   Answer: B) Cl > F > Br > I

Explanation: Although fluorine is more electronegative, chlorine has a slightly higher electron affinity than fluorine due to less electron-electron repulsion in its relatively larger size. Hence, the correct order is Cl > F > Br > I.

5. Which of the following oxides is amphoteric?
   A) Na₂O
   B) Al₂O₃
   C) SO₂
   D) CaO
   Answer: B) Al₂O₃

Explanation: Amphoteric oxides can act as both acids and bases. Aluminum oxide (Al₂O₃) is an amphoteric oxide, meaning it can react with both acids and bases to form salts and water.

6. The first ionization energy generally:
   A) Increases across a period
   B) Decreases across a period
   C) Decreases down a group
   D) A and C
   Answer: D) A and C

Explanation: Ionization energy increases across a period due to increasing nuclear charge, which pulls electrons closer, making them harder to remove. It decreases down a group because the outer electrons are further from the nucleus and are more easily removed.

7. Which of the following is the most electronegative element?
   A) Oxygen
   B) Fluorine
   C) Nitrogen
   D) Chlorine
   Answer: B) Fluorine

Explanation: Fluorine is the most electronegative element in the periodic table, as it has the greatest tendency to attract electrons towards itself when forming a bond.

8. Which group in the periodic table contains elements that are all nonmetals?
   A) Group 2
   B) Group 14
   C) Group 18
   D) Group 15
   Answer: C) Group 18

Explanation: Group 18 consists of the noble gases (e.g., helium, neon, argon), which are all nonmetals. These elements are characterized by their lack of reactivity due to having a complete valence shell.

9. The d-block elements are also known as:
   A) Alkali metals
   B) Transition elements
   C) Noble gases
   D) Metalloids
   Answer: B) Transition elements

Explanation: The d-block elements, located in groups 3–12 of the periodic table, are also referred to as transition elements. These elements typically form colored compounds and exhibit variable oxidation states.

10. Which of the following statements is true about the modern periodic table?
    A) Elements are arranged in order of decreasing atomic masses
    B) Elements are arranged in order of increasing atomic numbers
    C) All elements in the same group have the same number of neutrons
    D) Elements are arranged in alphabetical order
    Answer: B) Elements are arranged in order of increasing atomic numbers

Explanation: In the modern periodic table, elements are arranged in order of increasing atomic numbers, which reflect the number of protons in the nucleus of each element. This arrangement accounts for the periodic recurrence of chemical properties.