Change set
Pick exam & year, then Go.
Question map
Not attempted
Correct
Incorrect
★
Bookmarked
Loading…
Q61
(CGS/2026)
Science & Technology › Basic Science (Physics, Chemistry, Biology)
What is the molarity of NaOH in the solution prepared by dissolving its 4 g in 250 ml of solution? (The atomic mass of sodium is 23)
Result
Your answer:
—
·
Correct:
B
Explanation
Molarity (M) is defined as the number of moles of solute dissolved in one litre of solution. The calculation for this problem is as follows:
- Step 1: Calculate the molar mass of NaOH. The atomic masses are Na = 23, O = 16, and H = 1. Therefore, Molar Mass = 23 + 16 + 1 = 40 g/mol.
- Step 2: Calculate the number of moles of NaOH. Moles = Given Mass / Molar Mass = 4 g / 40 g/mol = 0.1 mol.
- Step 3: Convert the volume of the solution to litres. Volume = 250 ml = 250/1000 L = 0.25 L.
- Step 4: Calculate Molarity. Molarity = Moles / Volume (L) = 0.1 mol / 0.25 L = 0.4 M.
The result is 0.4 M. In the provided options, '0-4 M' is a typographical representation of 0.4 M.
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.
75%
got it right
✓ Thank you! We'll review this.