Q. 7.14 - An Introduction to General, Organic, and Biological Chemistry

Question

Calculate the molar mass for each of the following : 

a. ${\mathrm{C}}_4{\mathrm{H}}_8{\mathrm{O}}_4$      b. ${\mathrm{Ga}}_2{\left({\mathrm{CO}}_3\right)}_3$     c. ${\mathrm{KBrO}}_4$

Step-by-Step Solution

Answer

a. The molar mass of ${\mathrm{C}}_4{\mathrm{H}}_8{\mathrm{O}}_4$ is $120 \mathrm{g}$

b. The molar mass of ${\mathrm{Ga}}_2{\left({\mathrm{CO}}_3\right)}_3$ is $319.38 \mathrm{g}$

c. The molar mass of ${\mathrm{KBrO}}_4$ is $240.38 \mathrm{g}$

Part (a) Step 1 : Given information

We have to calculate the molar mass of  ${\mathrm{C}}_4{\mathrm{H}}_8{\mathrm{O}}_4$

Part (a) Step 2 : Simplification

We know that,

Molar mass of one $\mathrm{C}$ atom = $12.01 \mathrm{g}$

Molar mass of one $\mathrm{H}$ atom =$1.00 \mathrm{g}$

Molar mass of one $\mathrm{O}$  atom = $15.99 \mathrm{g}$

So, molar mass of ${\mathrm{C}}_4{\mathrm{H}}_8{\mathrm{O}}_4$ =$4\left(12.01\right) + 8\left(1.00\right) + 4\left(15.99\right)$ = $120 \mathrm{g}$

Part (b) Step 1 : Given information

We have to calculate the molar mass of  ${\mathrm{Ga}}_2{\left({\mathrm{CO}}_3\right)}_3$

Part (b) Step 2 : Simplification

We know that,

Molar mass of one $\mathrm{Ga}$ atom = $69.72 \mathrm{g}$

Molar mass of one $\mathrm{C}$ atom = $12.01 \mathrm{g}$

Molar mass of one $\mathrm{O}$ atom = $15.99 \mathrm{g}$

So, molar mass of ${\mathrm{Ga}}_2{\left({\mathrm{CO}}_3\right)}_3$= $2\left(69.72\right) + 3\left(12.01\right) + 9\left(15.99\right)$ = $319.38 \mathrm{g}$

Part (c) Step 1 : Given information

We have to calculate the molar mass of  ${\mathrm{KBrO}}_4$

Part (c) Step 2 : Simplification

We know that,

Molar mass of one $\mathrm{K}$ atom = $39.09 \mathrm{g}$

Molar mass of one $\mathrm{Br}$  atom = $137.33 \mathrm{g}$

Molar mass of one $\mathrm{O}$ atom = $15.99 \mathrm{g}$

So, molar mass of ${\mathrm{KBrO}}_4$ = $39.09 + 137.33 + 4\left(15.99\right)$ = $240.38 \mathrm{g}$