Question

Pick the correct statements.
(I) The repeating unit of polyacetylene contains $C=C$ bond .
(II) Acetylene ozonide involves $s{{p}^{3}}-s{{p}^{3}}$ overlap.
(III) Alkyne with maximum number of acidic hydrogen atoms is ethyne.
(IV) Ozonolysis product of acetylene product of acetylene is a dial.
(A) $I,II,III$
(B) $II,III,IV$
(C) $I,II,III,IV$
(D) $I,IV$

Answer 1

We know that Alkynes are the unsaturated hydrocarbons that consist of at least one triple bond between the carbon atoms. There are two types of alkynes named terminal alkynes and internal alkynes. Terminal alkynes are the triple bonded compounds in which the carbon atom shares a triple bond with the carbon which lies at the end of the chain. Internal alkynes are the compounds in which the triple bond lies in between the two carbon atoms, neither of which are terminal.

Complete answer:
The structure of the alkyne has uniqueness in it due to the presence of hybridization. The acidity of alkynes, the non-polar bonding strength, and the linearity in them is because of the triple bonds in the alkynes. The alkyne compounds are slightly soluble in the polar solvents and are completely insoluble in water.
The repeating unit of polyacetylene contains the $C=C$ bond. A section of polyacetylene can be represented as $-CH=CH-CH=CH-CH=CH-CH=CH-CH=CH-CH=CH-$
Acetylene ozonide involves $s{{p}^{3}}-s{{p}^{3}}$ overlap as only single bonds are present. No multiple bonds are present.
Alkyne with maximum number of acidic hydrogen atoms is ethyne $H-C\equiv C-H$ It has two acidic hydrogen atoms.
Ozonolysis product of acetylene is a dial, $H-C\equiv C-H{{O}_{3}}\xrightarrow[Ozonolysis]{{{O}_{3}}}OHC-CHO$
Therefore, the correct answer is option C.

Note:
Remember that these triple bonded alkyne compounds possess a boiling point which is slightly higher than those of the alkanes and alkenes. For example, the boiling point of ethane is $-88.6{}^\circ C$ whereas that of ethene is $-103.7{}^\circ C.$ Ethyne has a slightly higher boiling point of $-84{}^\circ C.$ The boiling point of alkynes increases with an increase in the number of carbon atoms.