Q. 6.104 - An Introduction to General, Organic, and Biological Chemistry

Question

Match each of the formulas (a to c) with the correct diagram (1 to 3) of its shape, and name the shape; indicate if each molecule is polar or non-polar. 

Step-by-Step Solution

Answer

a. Formula ${\mathrm{PBr}}_3$ corresponds to shape $2$. It has trigonal pyramidal shape. It is a  polar molecule.  

b. Formula ${\mathrm{SiCl}}_4$ corresponds to shape $3$. It has tetrahedral shape. It is non-polar molecule.  

c. Formula ${\mathrm{OF}}_2$ corresponds to shape $1$. It has bent shape. It is a polar molecule.  

Part(a) Step 1: Given information

We have been given the formula of ${\mathrm{PBr}}_3$.

We need to find the correct diagram from 1 to 3 of its shape, name the shape; and also indicate whether the molecule is polar or non-polar. 

Part(a) Step 2: Explanation

The formula ${\mathrm{PBr}}_3$ corresponds to shape $2$.

It has $3$ bonds attached to central atom- Phosphorus and $1$ lone pair electron on central atom. Its shape is trigonal pyramidal with bond angles$<109.5°$ . It is a polar molecule.

Part(b) Step 1: Given information

We have been given the formula of ${\mathrm{SiCl}}_4$.

We need to find the correct diagram from 1 to 3 of its shape, name the shape; and also indicate whether the molecule is polar or non-polar. 

Part(b) Step 2: Explanation

The formula ${\mathrm{SiCl}}_4$ corresponds to shape $3$. It has $4$ bonds attached to central atom- Silicon and no lone pair electron on central atom. Its shape is tetrahedral with bond angles $109.5°$. It is a non-polar molecule.

Part(c) Step 1: Given information

We have been given the formula of ${\mathrm{OF}}_2$.

We need to find the correct diagram from 1 to 3 of its shape, name the shape; and also indicate whether the molecule is polar or non-polar. 

Part(c) Step 2: Explanation

The formula ${\mathrm{OF}}_2$ corresponds to shape $1$. It has $2$ bonds attached to central atom- Oxygen and $2$ lone pair electron on central atom. Its shape is bent because of presence of $2$ lone pairs of electron and its bond angle is $103°$. It is a polar molecule.