In valence bond theory, orbital hybridisation is the concept of mixing atomic orbitals to generate new hybrid orbitals (with different energies, shapes, and other properties than the atomic orbitals) suited for electron pairing to form chemical bonds. The organic chemical compound ethyne, often known as acetylene, has the chemical formula C2H2. This substance is a hydrocarbon since its entire chemical composition consists only of hydrogen and carbon atoms.
A triple bond exists between two carbon atoms, each singly connected to one other hydrogen atom in the ethyne molecule. It’s worth noting that all four atoms are aligned in a straight line with bond angles of around 180 degrees. It’s also worth noting that the carbon-hydrogen bond length in the ethyne molecule is roughly 106 picometres, but the carbon-carbon bond length in the molecule is nearly 120.3 picometres.
All four atoms in this molecule are in a straight line. The hybridisation of ethyne questions shows that the triple link between carbon and carbon is only 1.20Å long. Both carbons are sp-hybridised in the hybrid orbital image of acetylene.
The 2s orbital joins with the 2px orbital to generate two sp hybrid orbitals aligned at an angle of 180° concerning each other in an sp-hybridised carbon (e.g. along the x-axis). The unhybridized 2py and 2pz orbitals are positioned perpendicularly along the y and z axes.
1s2 2s2 2p2 represents the electrical arrangement of carbon in its ground state. When it is exciting, one of the electrons from the 2s orbital moves or jumps to the 2pz orbital, changing the electrical configuration to 1s2 2s1 2px1 2py1 2pz1.
Because the CH molecule only contains one hydrogen atom, the 2s1 and 2pz1 orbitals become hybridised. Each CH molecule will produce two hybridised sp orbitals, resulting in the production of four sp hybridised orbitals.
When one sp orbital from each carbon overlaps with the 1s orbital of hydrogen during hybridisation, a C-C sigma bond is produced, and two C-H bonds are generated when the second sp orbital from each carbon overlaps with the 1s orbital of hydrogen.
The carbon atom will have two half-filled 2p orbitals in this configuration. Instead of participating in the hybridisation, these two pairs of p orbitals form two pi bonds, resulting in the formation of a triple bond.
Things to remember about hybridisation of ethyne
Furthermore, it is important to note while solving hybridisation of ethene questions that:
- The ethyne molecule is sp hybridised because it has one sigma and two carbon-carbon pi bonds.
- The carbon atom requires extra electrons to establish four bonds with hydrogen and other carbon atoms to create C2H2. As a result, one 2s2 pair is shifted to the 2pz orbital, which is now unoccupied.
- Each carbon’s 2s orbital combines with one of the 2p orbitals to generate two sp hybrid orbitals.
- Between the two carbon atoms in ethyne, there is a triple bond.
- Each CH molecule forms two hybridised sp orbitals, resulting in the production of four sp hybridised orbitals.
- When one sp orbital from each carbon overlaps with the 1s orbital of hydrogen during hybridisation, a C-C sigma bond is produced, and two C-H bonds are generated when the second sp orbital from each carbon overlaps with the 1s orbital of hydrogen. The carbon atom will have two half-filled 2p orbitals in this configuration.
- Instead of participating in the hybridisation, these two pairs of p orbitals form two pi bonds, resulting in the formation of a triple bond.
Hybridisation of Ethyne Importance
One of its most notable applications of ethyne is in oxyacetylene gas welding and oxyacetylene gas cutting because ethyne burns with a very hot flame. When ethyne is subjected to combustion with oxygen, the flame created is known to have a temperature of roughly 3600 Kelvin.
Acetylene is also used to make a variety of polyethene polymers. When ethyne undergoes semi-hydrogenation, it transforms into ethylene (ethene). The ethylene produced as a byproduct of this reaction can be used as a feedstock in polymerisation operations to produce polyethene as the end product.
It is also used in the production of portable lighting. For use in mining activities, calcium carbide is often combined with water to generate acetylene, which is used in lamps.
Conclusion
Ethyne is considered to be the simplest alkyne because it just has two carbon atoms that are triple linked to each other. Ethyne, often known as acetylene, has the chemical formula C2H2. This substance is a hydrocarbon since its entire chemical composition consists only of hydrogen and carbon atoms. A triple bond exists between two carbon atoms, each singly connected to one other hydrogen atom in the ethyne molecule. Thus all four atoms are aligned in a straight line with bond angles of around 180 degrees. The ethyne molecule is sp hybridised because it has one sigma and two carbon-carbon pi bonds.
Ethyne is used in oxyacetylene gas welding and oxy acetylene gas cutting, making polyethene polymers and producing portable lighting. Thus, through these notes, we have learned the importance of the Hybridisation of Ethyne and discussed solving the hybridisation of ethene questions.
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