Question

The chemical formula for marsh gas (methane) is:
a.) \[{C_2}{H_6}\]
b.) \[C{H_4}\]
c.) \[{C_3}{H_8}\]
d.) \[{C_4}{H_{10}}\]

Answer 1

Hint: Marsh gas (methane) is the simplest alkane. It is the main constituent of natural gas. It is also known as hydrogen carbide.

Complete step by step solution:
Methane or marsh gas is a chemical compound with chemical formula \[C{H_4}\]. It is the simplest alkane and the main constituent of natural gas. In the structure of methane, the central atom Carbon is \[s{p^3}\] hybridized and the four surrounding hydrogens are connected to the central atom carbon by sigma bonds. The Carbon-Hydrogen bond length is approximately 108.7 pm (1 pm = \[{10^{ - 12}}m\]) and the bond angle between any two hydrogens is. The shape of the molecule is a tetrahedron.

Additional Information: Methane is found in small quantities in the Earth’s atmosphere. It is flammable and is used as a fuel worldwide. When methane is burned in the presence of oxygen, it releases carbon dioxide and water vapours. The chemical reaction demonstrating the above change is given below:

\[C{H_4} + 2{O_2} \to C{O_2} + 2{H_2}O\]

Methane is an important greenhouse gas. It has such a good heat absorbing effect. Naturally occurring methane is found both below ground and under the seafloor, and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane.
At room temperature and standard pressure, methane is a colourless, odourless gas.

Note: It must be remembered that methane consists of one carbon only, which its IUPAC name suggests. The IUPAC name of \[{C_2}{H_6}\] is ethane, \[{C_3}{H_8}\] is propane and so on.