Gobar gas, also known as biogas, is produced from animal and plant waste through a process called anaerobic digestion. This process involves the decomposition of organic matter by bacteria in the absence of oxygen. The resulting biogas is primarily composed of methane, along with small amounts of other gases such as carbon dioxide and trace elements.

Composition of Gobar Gas:
- Methane: The main component of gobar gas is methane (CH4), which typically makes up around 50-70% of the gas. Methane is a potent greenhouse gas and is also a valuable source of energy.
- Carbon Dioxide: Carbon dioxide (CO2) is another significant component of gobar gas, usually comprising 30-45% of the gas. While carbon dioxide is also a greenhouse gas, it is less potent than methane.
- Trace Gases: Gobar gas may also contain trace amounts of other gases such as hydrogen (H2), nitrogen (N2), hydrogen sulfide (H2S), and water vapor (H2O). These gases are present in smaller quantities and do not significantly contribute to the overall composition of the gas.

Formation of Methane:
The anaerobic digestion process involves several stages where different types of bacteria break down the organic matter in animal and plant waste. During the initial stages, complex organic compounds are broken down into simpler compounds, including volatile fatty acids and alcohols. In the final stage, methanogenic bacteria convert these compounds into methane and carbon dioxide through a process called methanogenesis.

Uses of Gobar Gas:
Gobar gas has several practical applications due to its high methane content. Some of the main uses of gobar gas include:
- Cooking: Gobar gas can be used as a clean and renewable source of energy for cooking purposes. It can be used in gas stoves or burners, providing a convenient and environmentally friendly alternative to fossil fuels.
- Heating: Gobar gas can also be used for heating applications, such as water heaters or space heaters. This can be particularly useful in rural areas where access to other forms of energy may be limited.
- Electricity Generation: Gobar gas can be used to generate electricity through the combustion of the gas in an internal combustion engine or a gas turbine. This can be an efficient way to produce renewable electricity for small-scale power generation.

In conclusion, gobar gas produced from animal and plant waste primarily contains methane, along with carbon dioxide and trace gases. The methane content makes gobar gas a valuable source of renewable energy with various practical applications.