Consider the following statements: I. In diamond, each carbon atom is $s p^3$-hybridised. II. Graphite has…
Consider the following statements:
I. In diamond, each carbon atom is $s p^3$-hybridised.
II. Graphite has planar hexagonal layers of carbon atoms.
III. Silicones being surrounded by non-polar alkyl groups are water repelling in nature
IV. The order of catenation in group 14 elements is $\mathrm{Si}>\mathrm{C}>\mathrm{Sn}>\mathrm{Ge}>\mathrm{Pb}$.
The correct statements are
I, II, III
II, III, IV
I, II, IV
I, III, IV
Solution
(I, II) In diamond, hybridisation of carbon is $s p^3$ and graphite has planar hexagonal layer of $\mathrm{C}$-atoms. The hybridisation of each $\mathrm{C}$-atom in graphite is $s p^2$.
(III) Silicones are organo-silicon polymers formed from inorganic and organic monomer having chemical formula $\left(R_2 \mathrm{SiO}ight)_n$, due to non-polar alkyl group, silicones are water repelling in nature.
(IV) The catenation tendency in group 14 elements decreases due to decrease in element bond strength. Thus, the correct order is
$$
\mathrm{C}>>\mathrm{Si}>\mathrm{Ge} \approx \mathrm{Sn}
$$
Hence, statement (IV) is incorrect.
Thus, option (a) is correct.
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