NEET Classification of Elements and Periodicity in Properties — Set 8

Question 1

Which of the following has the smallest atomic radius among group 15 elements?

Accepted Answer

Atomic radius increases down a group. Among N, P, As, and Sb (group 15), N (period 2) has the smallest radius.

Question 2

Which of the following elements exhibits variable valency due to d-orbital involvement?

Accepted Answer

d-block elements exhibit variable valency due to partially filled d-orbitals. Cu (group 11) shows this, unlike Na (s-block), Al (p-block), or Kr (p-block, full).

Question 3

Which element has a positive electron gain enthalpy?

Accepted Answer

Noble gases have positive electron gain enthalpies due to their stable configurations. Ne (group 18) requires energy to add an electron, unlike O, S, or Cl.

NEET Chemistry: Classification of Elements and Periodicity in Properties — Practice Set 8

Q1. Which of the following has the smallest atomic radius among group 15 elements?

Q2. Which of the following elements exhibits variable valency due to d-orbital involvement?

Q3. Which element has a positive electron gain enthalpy?

Q4. Which of the following elements has the highest electronegativity?

Q5. Which d-block element in period 4 forms a compound with oxygen exhibiting the highest oxidation state of +7?

Q6. Which oxide among the following is basic?

Q7. Which element has the smallest ionic radius among the following cations?

Q8. Which element was predicted as Eka-aluminium by Mendeleev?

Q9. Which pair of elements belongs to the same period?

Q10. Which element in group 1 has the lowest first ionization enthalpy?