The correct statement is

Question

The correct statement is (A) The extent of actinoid contraction is almost the same as lanthanoid contraction. (B) Ce+4 in aqueous solution is not known. (C) The earlier members of lanthanoid series resemble calcium in their chemical properties. (D) In general, lanthanoids and actinoids do not show variable oxidation states

Tardigrade Admin · Accepted Answer

The earlier members of lanthanoid series resemble calcium in some of their chemical properties. e.g., Hydroxide of both of them are ionic and basic.

Q. The correct statement is

The extent of actinoid contraction is almost the same as lanthanoid contraction.

$C e^{+ 4}$ in aqueous solution is not known.

The earlier members of lanthanoid series resemble calcium in their chemical properties.

In general, lanthanoids and actinoids do not show variable oxidation states

The earlier members of lanthanoid series resemble calcium in some of their chemical properties. e.g., Hydroxide of both of them are ionic and basic.