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QJEEM21Cheeb4: JEE Main 2021 Chemistry - Class 11 JEEM21Cheeb4 Solution: The exact volumes of 1 M NaOH solution required to neutralise…
The exact volumes of 1 M NaOH solution required to neutralise 50 mL of 1 M H3PO3 solution and 100 mL of 2 M H3PO2 solution, respectively, are :
Multiple Choice Options
- A 100 mL and 50 mL
- B 100 mL and 200 mL
- C 100 mL and 100 mL
- D 50 mL and 50 mL
Step-by-Step Verified Solution

Millimoles of H3PO3 = M
For 1 millimole of H3PO3, we require 2 millimoles of NaOH.
For 50 millimole of H3PO3, we require (2
Millimoles of NaOH = M
1
V = 100 mL

Millimoles of H3PO2 = M
For 1 millimole of H3PO2, we require 1 millimoles of NaOH.
For 200 millimoles of H3PO2, we require 200 millimoles of NaOH.
So, volume of NaOH = 200 mL