Chapter 22.1, Problem 6R

To determine

To Calculate: Themolecular mass of acetylsalicylic acid.

Answer to Problem 6R

The molecular mass of acetylsalicylic acid ( ${\text{HOOC-C}}_6{\text{H}}_4{\text{-OOCCH}}_3$ ) is $\text{180 amu}$ .

Explanation of Solution

Given:

Chemical formula of acetylsalicylic acid is ${\text{HOOC-C}}_6{\text{H}}_4{\text{-OOCCH}}_3$

Calculation:

As per the problem,

The chemical formula of acetylsalicylic acid is ${\text{HOOC-C}}_6{\text{H}}_4{\text{-OOCCH}}_3$

Molecular mass of Hydrogen, $\text{H=1 amu}$

Molecular mass of Oxygen, $\text{O=16 amu}$

Molecular mass of Carbon, $\text{C=12 amu}$

To calculate the molecular mass of acetylsalicylic acid, put the masses of hydrogen, oxygen and carbon in the chemical formula.

Molecular mass of acetylsalicylic acid ( ${\text{HOOC-C}}_6{\text{H}}_4{\text{-OOCCH}}_3$ )

  $\begin{array}{l}=8(\text{H)+4(O)+9(C)}\\ \text{=8(1 amu)+4(16 amu)+9(12 amu)}\\ \text{=8 amu+64 amu+108 amu}=180\text{ amu}\end{array}$

Conclusion:

The molecular mass of acetylsalicylic acid ( ${\text{HOOC-C}}_6{\text{H}}_4{\text{-OOCCH}}_3$ ) $\text{=180 amu}$ .