10 mL of a solution of NaOH is found to be completely neutralised by 8 mL of a given solution of HCl. If we take 20 mL of the same solution of NaOH, the amount HCl solution (the same solution as before) required to neutralise it will be :

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Chapter 2

NCERT

Class 10

Science

Solutions

3. 10 mL of a solution of NaOH is found to be completely neutralised by 8 mL of a given solution of HCl. If we take 20 mL of the same solution of NaOH, the amount HCl solution (the same solution as before) required to neutralise it will be :

Question:

10 mL of a solution of NaOH is found to be completely neutralized by 8 mL of a given solution of HCl. If we take 20 mL of the same solution of NaOH, the amount HCl solution (the same solution as before) required to neutralize it will be :

(a) 4 ml (b) 8 ml

(c) 12 ml (d) 16 ml

Answer:

d) 16 ml

Explanation: HCL reacts with NaOH to form NaCl + H₂O. 8 mL of HCL (hydrochloric acid) solution completely neutralises 10 mL of NaOH (sodium hydroxide). The amount of NaOH solution has been doubled in the questions; thus, the amount required of the HCL solution will also be doubled. 16 mL of HCL (hydrochloric acid) solution completely neutralises 20 mL of NaOH (sodium hydroxide).

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