Methane is one of the greenhouse gases and a primary constituent of natural gas. It absorbs outgoing heat radiation from the earth and thus contributes to the greenhouse effect. This is the reason so considered a greenhouse gas.
Methane remains in the atmosphere for approximately 10 years. It is twenty times more effective in trapping heat in comparison to carbon dioxide. Methane is emitted from a variety of natural and human influenced sources like landfills, natural gas and petroleum systems, agricultural activities, coal mining, stationary and mobile combustion, waste water treatment, and certain industrial process. Methane is an important energy source so efforts to prevent or utilize methane emissions can provide significant economical and environmental benefits.
Is Methane Ch4 is Ionic or Covalent Bond?
Ch4 methane gas is a covalent bond in which hydrogen, as well as carbon, share the valence electrons to full fill their outermost shell. Carbon and hydrogen both atoms have high electron affinity and high ionization energy. This means both of the atoms are not ready to lose valence electrons to complete the outermost Octet. So, the Ionic bond is not possible and involve in the CH4 methane gas molecule.
It should be noted here that methane gas covalent bond takes place in order to attain inert gas configuration. Four hydrogen atoms and one carbon atom alone cannot achieve the Independent state. The reason because all total five atoms do not have a fully completed outermost shell.
For accomplishing their need of becoming stable in nature they certainly join another atom with the contribution of outermost electrons.
Why Methane as Mash Gas
- Marsh gas is formed at the bottom of marshes due to the fermentation of cellulose by a special type of bacteria.
- It is also present in the air exhaled by animals whose food contains cellulose.
- It is contained in intestinal gases and in the blood of animals and human beings.
- Cavities in coal contain 90% methane. It is called ‘fire-damp.
- Methane is produced also by dry distillation of wood, peat (coal).
How Methane CH4 Covalent/Molecular Bond Formed?
As we said earlier in previous articles, hydrogen has a very unique behaviour. With some of the elements of the periodic table, it starts acting like metal while bonding with others it behaves like a non-metal.
In the formation of methane gas, the hydrogen atoms is participating in the bond as a nonmetal. Also, carbon belongs to the 14 group of the periodic table, a non-metal however it reflects a few metalloid properties.
Both of these atoms share their electrons forms a single bond.
Let’s take a look, Carbon has an atomic number 6 and a mass number 12 amu. If we look at its electronic configuration, it has two shells k and L.
- Carbon = K, L=2,4
If we look at hydrogen, we all know its atomic number is 1 and its mass number is is 2amu. Now if we carefully see here it has one electron only in the K shell
As I said to you earlier, you should remember, both of the atoms want to achieve the nearest noble gas configuration.
Carbon has the inert nearest configuration to neon ( atomic no 10= k, L= 2,8) where has hydrogen closest inert gas is helium (atomic no 2=k=2)
Both of these atoms share their electrons with each other and attain noble gas equivalent configuration becomes stable and turn out to be a covalent molecule.
This structure can be represented with dots and cross diagrams. This structure was recommended by Lewis. It is the easiest way to understand how both of the atoms contribute electrons to accomplish each other needs.
During the representation, it should be noted that dots and cross are represented as electrons whereas a simple circle represents energy shells named K, L, M, N. When one circle overlaps The other it means sharing of electrons takes place.
Structure of Methane
The methane molecule is three-dimensional. The four outer electrons in the carbon atom move as far apart from each other as possible because electrons repel each other (remember that particles with similar charges always repel each other). It is a fact that the electrons will have the greatest distance between themselves when the carbon-hydrogen bonds are in the shape of a tetrahedron. A tetrahedron (‘tetra’ is a Greek word meaning “four”) is pyramid-shaped.
These kinds of structures can also be represented by drawing a simple straight line between two different or similar atoms.
Straight line represents the type of Bond. if it is one straight line, it means a single bond, if it is two or 3 it means there is a double and triple covalent Bond.
Facts Of Methane Gas
- Methane is a source of carbon monoxide and hydrogen.
- It is used in the preparation of useful compounds like ethyne (acetylene), methanal
- It is a colourless and an odourless gas.
- Its melting point is -183 °C and its boiling point is -162 °C.
- It is negligibly soluble in water and soluble in organic solvents.
What others are Reading?
- Is Hydrogen chloride (HCl) an Ionic or Covalent Bond or Metallic?
- Is Water H2O an Ionic or Covalent Bond
- Is Sodium Chloride NaCl Ionic or Covalent or Metallic?
- MgCl2 Ionic or Covalent Bond?
- Carbon Dioxide CO2 Ionic or Covalent Bond?
- Is Covalent Bond Stronger than an Ionic Bond?-A Complete Guide