Change set
Pick exam & year, then Go.
Question map
Not attempted
Correct
Incorrect
★
Bookmarked
Loading…
Q57
(CISF/2025)
Science & Technology › Basic Science (Physics, Chemistry, Biology)
Which one of the following acids has the highest pH value ?
Result
Your answer:
—
·
Correct:
A
Explanation
The pH value is a measure of the hydrogen ion concentration [H+] in a solution, defined as pH = -log[H+]. A higher pH value indicates a lower concentration of hydrogen ions, characteristic of a weaker acid.
- Nitric acid (HNO3), Sulphuric acid (H2SO4), and Hydrochloric acid (HCl) are strong acids. They dissociate almost completely in water, producing high concentrations of H+ ions and resulting in very low pH values (near 0 or even negative for 1 M concentrations).
- Acetic acid (CH3COOH) is a weak organic acid. It only partially ionizes in aqueous solution. At 1 M concentration, its [H+] is much lower (approx. 0.0042 M) compared to strong acids, resulting in a significantly higher pH value (approximately 2.4).
Since Acetic acid has the lowest concentration of hydrogen ions among the options, it has the highest pH value.
How others answered
Each bar shows the % of students who chose that option.
Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
0%
got it right
✓ Thank you! We'll review this.
SIMILAR QUESTIONS
Which one of the following is a tribasic acid?
Which one of the following is an organic acid?
Which one of the following has the highest ionic character? (a) BeF3 (b) SiO2 (c) NCl3 (d) K2S
A solution has a pH value around 13-0. The solution may be called