Question

Question: What orbitals are used to form each bond in the following molecules?

$$\begin{gathered} \mathbf{a}\mathbf{.}\mathbf{}{\mathbf{CH}}_{\mathbf{3}}\mathbf{BeH} \\ \mathbf{b}\mathbf{.}{\left({\mathrm{CH}}_3\right)}_{\mathbf{3}}\mathbf{B} \\ \mathbf{c}\mathbf{.}\mathbf{}{\mathbf{CH}}_{\mathbf{3}}{\mathbf{OCH}}_{\mathbf{3}} \end{gathered}$$

Short answer

Answer

a. CH₃BeH

The carbon-hydrogen bonds are formed by sp³ hybridized orbital of carbon and the 1s orbital of hydrogen.

The carbon-beryllium (C-Be) bond involves the carbon’s sp³ hybridized orbital and beryllium’s sp hybridized orbital.

b. (CH₃)₃B

The carbon-boron bond involves the carbon’s sp³ hybridized orbital and boron’s hybridized orbital.

The carbon-hydrogen bonds are formed by the carbon’s sp³ hybridized orbital and hydrogen’s 1s orbital.

c. CH₃-O-CH₃

The carbon-oxygen bond involves the carbon’s sp³ orbital and the oxygen’s orbital.

The carbon-hydrogen bonds involve the carbon’s sp³ hybridized orbital and the hydrogen’s 1s orbital.

Step-by-step solution

Step-by-Step Solution Step 1: Lewis Structures 

The Lewis structure illustrates the bonding in a molecule. It represents the atoms, and the bonding and non-bonding electrons present in the molecule.

Hybridization of atoms

The process of formation of hybrid orbitals by intermixing atomic orbitals is referred to as hybridization.The hybridization of each atom in a molecule can be determined by considering the number of groups bonded to it.

If an atom is bonded to four other atoms/groups, then it is hybridized. If it is bonded to three groups, then it is sp³ hybridized, and if bonded to two other groups, then it is sp² hybridized.

Lewis structures of the given molecules

The Lewis structures of the given molecules are as follows:

Lewis structure of ${\mathrm{CH}}_3\mathrm{BeH}$.

Lewis structure of (CH₃)₃B .

Lewis structure of CH₃-O-CH_3.

The orbitals used for bonding

a. In the Lewis structure of ${\mathrm{CH}}_3\mathrm{BeH}$, all carbon atoms are bonded to four other atoms. Therefore, they are${\mathrm{sp}}^3$ hybridized.

The orbitals used to form the carbon-hydrogen bond in ${\mathrm{CH}}_3\mathrm{BeH}$are the sp³ hybridized orbital of carbon and the 1s orbital of hydrogen.

The beryllium atom in CH₃BeH is bonded to two other atoms, and hence, it is hybridized.

The carbon-beryllium bond involves the sp³ hybridized orbital of carbon and the sp hybridized orbital of beryllium.

b. The boron atom in (CH₃)₃B is connected to three other groups, and hence, it is sp² hybridized. The carbon-boron bond involves the sp³ hybridized orbital of carbon and the sp² hybridized orbital of boron.

The carbon atoms are bonded to four other atoms, and therefore, they are sp³ hybridized. The carbon-hydrogen bonds are formed by the sp³ hybridized orbital of carbon and the 1s orbital of hydrogen.

c. The oxygen atom in CH₃-O-CH₃ is connected to two other atoms. It bears two lone pairs of electrons and hence is sp³ hybridized.

The carbon-oxygen bond involves the sp³ orbital of both carbon and oxygen.

All carbon atoms are bonded to four other atoms, and therefore, they are sp³ hybridized. The carbon-hydrogen (C-H) bonds are formed by the carbon’s sp³ hybridized orbital and the hydrogen’s 1s orbital.