Question

Hydrocarbons 1. react with oxygen to give H2 and CO2 plus heat. 2. react to give only water and carbon dioxide in every instance. 3. are compounds of carbon, hydrogen, and oxygen. 4. are compounds composed only of carbon and hydrogen.

Answer 1

The correct answer is option 4.

Step-by-step explanation:

Hydrocarbons are defined as molecule composed of carbon and hydrogen atoms.They are of two types:

Saturated hydrocarbons : These are the hydrocarbons in which only single bond between carbon- carbon atoms is present.

Unsaturated hydrocarbons : These are the hydrocarbons in which double or triple bond between carbon- carbon atoms is present.

Combustion reaction is defined as the chemical reaction in which a hydrocarbon reacts with oxygen gas to produce carbon dioxide gas and water molecule.

`\text{hydrocarbon}+O_2\rightarrow CO_2+H_2O`

For example:

`C_3H_8+5O_2\rightarrow 3CO_2+4H_2O`