Methane Kundanpuri

Presented By 10th

Class of Govt. Sen. Sec. School, Kundan Puri, Ludhiana

Methane

Lets talk about Methane gas ………………

What is Methane???? Methane is the simplest hydrocarbon. It is the first member of the homogeneous series of alkanes. Its molecular formula is CH4 And its molecular mass is 16. The valency of carbon in methane is 4 and that of each hydrogen is one.

Structure of Methane molecule Electronic configuration of carbon atom is 2,4. Therefore, its valence shell has 4 electrons. For completing its octet of 8 electrons in the valence shell for attaining stable configuration of neon.

2 4

Formation and Representation of Methane Molecule H C

H

H

C H

H

Structural Formula of Methane H

H

C

H

H

Shape of Methane Molecule It has been observed that methane molecule is not plane but has three dimensional structure. Infact, methane molecule is tetrahedral in shape. All the four faces of a regular tetrahedron are bounded by equilateral triangles. In methane molecule, carbon atom is located at the center of a regular tetrahedron and four hydrogen atoms are occupying the four corners of the tetrahedron.

H

C

H

H

H

Sources of Methane…  

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One big and natural source of methane gas is natural gas. Methane gas is formed by bacterial decomposition of marshy plants and animal material under water. It comes out of water in the form of bubbles that is why methane gas is also called marsh gas. Biogas, gobar gas and sewage gas formed by decomposition of animal dung, and plant material have methane gas has major constituent. Methane gas is one of the constituent of coal gas. The gases coming out of coal mines contains a lot of methane gas.

Physical properties of Methane Gas  It

is colourless, odourless and tasteless.  It is lighter than air.  It is insoluble in water but soluble in ether, alcohol, acetone and carbon tetrachloride.  Methane Gas shows green house effect. Infact, molecule of methane traps twenty times as much the heat radiations as that trapped by a molecule of carbon dioxide.

Chemical Properties of Methane Gas  CH4+

2O2

methane oxygen energy

 Methane

on burning

CO2+ 2H2O + Heat

carbon-dioxide water

is quite unreactive because it is saturated hydrocarbon.  Methane neither decolourises bromine water nor acidified potassium permanganate solution.  Methane does not undergo polymerisation as it is saturated hydrocarbon.

Uses of Methane…… 

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Methane is used as domestic and industrial fuel as it liberates lot of heat on burning in air without producing smoke. Carbon black and hydrogen are produced by decomposing methane. Carbon black is used as filter in tyre industry and hydrogen for manufacturing. It is used to prepare a large number of industrial compounds such as CHCL3, CCL4, HCHO etc. Methane is the main constituent of natural gas which is used as non-polluting automobile fuel in the form of compressed natural gas (CNG). Biogas and coal gas which are used as fuel contain significant part of Methane.