MCQ
The lanthanoid that does NOT show $+4$ oxidation state is
- ADy
- ✓Eu
- CCe
- DTb
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[Given $K _{ b }$ for $\left.\left( H _{2} O \right)=0.52\, K\, kg\, mol ^{-1}\right]$
$Q (47 \%)$ and $R (2 \%)$. The major product(s) of the following reaction sequence is (are)
$\begin{array}{l}\begin{array}{ll}\text { 1) } Ac _2 O \text {, pyridine } \quad \text { 1) } Sn / HCl \end{array} \\ R \xrightarrow{2) Br _2, CH _3 CO _2 H } S \quad \xrightarrow{2) Br _2 / H _2 O \text { (excess) }} \text { major product(s) } \\ \text { 3) } H _3 O ^{+} \quad \text {3) } NaNO _2, HCl / 273-278 K \\ \text { 4) } NaNO _2, HCl / 273-278 K \quad \text { 4) } H _3 PO _2 \\ \text { 5) } EtOH , \Delta \\\end{array}$
$C{H_3}C{H_2}C{H_2}Br$ $\xrightarrow{{KOH(alc.)}}\,(A)\,\xrightarrow{{HBr}}(B)\,$ $\xrightarrow{{KOH(aq.)}}(C)$ The product $(C)$ is