JEE Main 2026 · 4 Apr · Shift 1 · Chemistry Q60

ChemistrySingle correct+4 / -1Question 60 of 75

The correct statements among the following are,

A. Mo(VI) and W(VI) are less stable than Cr(VI).

B. $\ce{Ce^{4+}}$ and $\ce{Tb^{4+}}$ are oxidant while $\ce{Eu^{2+}}$ and $\ce{Yb^{2+}}$ are reductant.

C. Cm and Am have seven unpaired electrons.

D. Actinoid contraction is greater from element to element than lanthanoid contraction.

Choose the correct answer from the options given below:

A and B Only

C and D Only

B and D Only

A and C Only

Answer and worked solution

Official answer: C

A ✗: down group 6 the higher oxidation states become more stable (Mo(VI), W(VI) > Cr(VI)).
B ✓: $\ce{Ce^{4+}}$ and $\ce{Tb^{4+}}$ (f⁰ / f⁷) are oxidants; $\ce{Eu^{2+}}$ and $\ce{Yb^{2+}}$ (f⁷ / f¹⁴) are reductants.
C ✗: Am ( $5f^7$ ) has 7 unpaired electrons but Cm ( $5f^76d^1$ ) has 8.
D ✓: the 5f electrons shield poorly, so the actinoid contraction per element is larger.

B and D.

(C)

Topics:Actinoids Lanthanoids Transition element properties

JEE Main 2026 · 4 Apr · Shift 1, Chemistry question 60