D And F Block Elements - Inorganic Chemistry - Chemistry Previous Year Questions

Observe the following $f$-block elements

$\mathrm{Eu}(Z=63) ; \mathrm{Pu}(Z=94) ; \mathrm{Cf}(Z=98)$;

$\operatorname{Sm}(Z=62) ; \mathrm{Gd}(Z=64) ; \mathrm{Cm}(Z=96)$

How many of the above have half-filled $f$-orbitals in their ground state?

Match the following

The correct answer is

$Y$ in the given sequence of reactions is

$$\begin{gathered} \mathrm{P}_4+x \mathrm{NaOH}+y \mathrm{H}_2 \mathrm{O} \xrightarrow{\mathrm{CO}_2} X+z \mathrm{NaH}_2 \mathrm{PO}_2 \\ X+\mathrm{CuSO}_4 \longrightarrow Y+\mathrm{H}_2 \mathrm{SO}_4 \end{gathered}$$

Identify the correct statements about lanthanoids

I. $\mathrm{Ce}^{4+}$ and $\mathrm{Tb}^{4+}$ act as oxidising agents.

II. $\mathrm{Eu}^{2+}$ and $\mathrm{Yb}^{2+}$ act as oxidising agents.

III. Misch metal is an alloy of $95 \%$ iron and $5 \%$ lanthanoid metal.

IV. $\mathrm{La}^{3+}$ and $\mathrm{Ce}^{4+}$ are diamagnetic in nature.

Consider the following pairs of elements and identify the pairs of elements which have nearly same atomic radius.

I. Y, La

II. Zr, Hf

III. Mo, W

IV. Cr, Mo

The pair of ions with paramagnetic nature and same number of electrons is

In which of the following transition metal ion (aquated) is not correctly matched with its colour?

Identify the correct statements from the following.

(i) Ti (IV) is more stable than Ti (III) and Ti (II).

(ii) Among $3 d$-series elements (From $Z=22$ to 29). Only copper has positive reduction potential $\left(M^{2+} / M\right)$.

(iii) Both Sc and Zn exhibit +1 oxidation state.