An unsaturated hydrocarbon us a hydrogen-carbon compound with

with double or triple carbon carbon bond between it's corresponding hydrocarbon or organic compound thus gives rise to alkene and alkyne

An unsaturated hydrocarbon is a hydrogen-carbon compound with one or more double or triple bonds of carbon-carbon atoms.

Explanation:

Generally hydrocarbons are compounds formed entirely by combination of carbon and hydrogen molecules. Hydrocarbons are classified as saturated and unsaturated hydrocarbons. A saturated hydrocarbons are those where the hydrogen-carbon molecules are formed with carbon-hydrogen single bond.

They are the simplest of hydrocarbons and the hydrogen atoms are dominant in them. While in unsaturated hydrocarbons, the number count of hydrogen atoms will be less to form bonds with carbon. So in unsaturated hydrocarbons, more number of carbon-carbon double or triple bonds are observed and less number of single bonds of C-H will be present.

B. It represents the change in enthalpy for the reaction.

Explanation:

The potential energy diagram for a chemical reaction shows its potential energy plotted against the reaction progress coordinate. The potential energy diagram shows how the potential energy of reactants and products vary as reactants are converted into products.

The potential energy of the system refers to energy stored in the chemical bonds of reactants and products. The difference between the potential energy of reactants and products is known as the enthalpy of reaction. This difference in potential energy may be positive or negative. A positive difference in potential energy implies an endothermic reaction while a negative difference in potential energy implies an exothermic reaction.