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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

JEE Main 2021 (Online) 16th March Evening Shift Chemistry - Some Basic Concepts of Chemistry Question 136 English Explanation 1

Millimoles of H3PO3 = M × V = 1 × 50 = 50

For 1 millimole of H3PO3, we require 2 millimoles of NaOH.

For 50 millimole of H3PO3, we require (2 × 50) = 100 millimoles of NaOH.

Millimoles of NaOH = M × V = 100

1 × V = 100

V = 100 mL

JEE Main 2021 (Online) 16th March Evening Shift Chemistry - Some Basic Concepts of Chemistry Question 136 English Explanation 2

Millimoles of H3PO2 = M × V = 2 × 100 = 200

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

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