Question

1. use the vsepr theory to predict the molecular geometry of the following molecules.

a. nf₃
b. sio₂
c. ch₄

Explanation:

Step1: Count electron domains for NF₃

N has 3 bonding pairs + 1 lone pair = 4 electron domains.

Step2: Assign electron geometry for NF₃

4 electron domains = tetrahedral electron geometry; 1 lone pair modifies molecular geometry to trigonal pyramidal.

Step3: Count electron domains for SiO₂

Si has 2 double bonding pairs + 0 lone pairs = 2 electron domains.

Step4: Assign geometry for SiO₂

2 electron domains = linear molecular geometry (no lone pairs to modify).

Step5: Count electron domains for CH₄

C has 4 bonding pairs + 0 lone pairs = 4 electron domains.

Step6: Assign geometry for CH₄

4 electron domains, no lone pairs = tetrahedral molecular geometry.

Answer:

a. NF₃: Trigonal pyramidal
b. SiO₂: Linear
c. CH₄: Tetrahedral