Question

The normal structure for ethyne(acetylene) is:
A. $H - C = C - H$
B. $H - C - C - H$
C. $H - C{H_2} - C{H_2} - H$
D. $H - C \equiv C - H$
E. $H - CH - CH - H$

Answer 1

Hint: Ethyne is a chemical name used for a chemical compound acetylene. The chemical formula of ethyne is ${C_2}{H_2}$. By the name “ethyne” itself it is known that the hydrocarbon chain is ethane as in ethane two carbon atoms are present.

Complete step by step answer:
The ethyne is commonly named as acetylene. The acetylene is a chemical compound with molecular formula ${C_2}{H_2}$. The ethyne contains two carbon atoms and two hydrogen atoms. The ethyne is the simplest alkyne in hydrocarbon. Acetylene is a colorless gas which is used in making fuels. It is unstable in its pure form that’s why it is used in the form of solution.
By the name ethyne, it can be determined that the hydrocarbon present in ethane. The suffix –yne is used for triple bonds.
Triple bond is the unsaturated chemical bond formed of one sigma and two pi bond.
In ethyne, one carbon atom is bonded to the other carbon atom by a triple bond and one carbon atom is bonded with one hydrogen by a single bond and another carbon atom is bonded with another hydrogen atom by a single bond.
Thus, from the given structure the correct structure of ethyne is shown below.
$H - C \equiv C - H$
Therefore, the correct option is D.

Note:
The carbon is a tetravalent compound as it contains four electrons in its valence shell. Thus it can share its four electrons with the other atoms to form four covalent bonds. While predicting the structure make sure that the tetravalency of carbon is fulfilled, else the structure is not correct.