Question

Bond angle present in the methane ($C{H}_4$) molecule is:
A.105${}^0$
B.107${}^0$
C.109${}^0$
D.110${}^0$

Answer 1

Hint: Methane molecule has ${sp}^3$ hybridization. Now try to figure out the value for the standard bond angle in this hybridization.

Complete step by step answer:
-Let’s talk about the $C{H}_4$ molecule. This is basically a combination of 1 carbon atom and 4 hydrogen atoms. However, to form this compound the central atom carbon has to complete its octet. It has 4 valence electrons and it obtains 4 more electrons from 4 hydrogen atoms. Hence, by sharing electrons between carbon and hydrogen there is a formation of a covalent bond.
-Now, we will discuss the hybridization of methane, the carbon here is ${sp}^3$ hybridized because one 2s orbital and three 2p orbitals in the valence shell of carbon combine to form four ${sp}^3$ hybrid orbitals that are of equal energy and also have equal shape. Further, four H atoms also use these four ${sp}^3$ hybrid orbitals of carbon to form four sigma bonds. It finally leads to the formation of the methane molecule.
-We have discussed the hybridization process. Now, determining the molecular geometry of methane should be easier for us. In methane, the four hybrid orbitals are located in such a manner so that they can decrease the force of repulsion between them. Hence, $C{H}_4$ acquires a tetrahedral shape.
Hence, the ${sp}^3$ hybrid orbitals have a bond angle of 109${}^0$28’. We can roughly assume it to be 109${}^0$.

Therefore, we can conclude that the correct answer to this question is option C.

Note:
All angles are the same in this compound with a bond length between all C-H bonds equal to 1.09 Angstrom. All the outer atoms are the same - the same dipoles, and that the dipole moments are in the same direction - towards the carbon atom, the overall molecule becomes non-polar. Therefore, methane has nonpolar bonds and is nonpolar overall.