Question

Which of the following acid has the highest concentration of ${\text{H}}^{+}$ ions?

• A. 1M hydrochloric acid
• B. 1M acetic acid
• C. 1M Citric acid
• D. 1M propanoic acid

Answer 1

The correct option is A

1M hydrochloric acid

Strong acids release ${\text{H}}^{+}$ ions more easily than weaker ones. Hydrochloric acid $(\text{HCl}$) is a strong acid, whereas, acetic acid $\left({\text{CH}}_3\text{COOH}\right)$, citric acid $\left({\text{C}}_6{\text{H}}_8{\text{O}}_7\right)$ and propanoic acid $\left({\text{CH}}_3{\text{CH}}_2\text{COOH}\right)$ are weak acids.
So, 1M hydrochloric acid will have a higher concentration of ${\text{H}}^{+}$ ions than acetic acid and propanoic acid.