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  9. Q38

RRB NTPC 2021 · Question 38 of 131

If a solution changes the colour of blue litmus paper to red, what will the pH of this solution be?

  1. Aless than 7Correct
  2. B14
  3. Cmore than 7
  4. D7

Answer: A. less than 7

Explanation

If a solution turns blue litmus red, its pH is likely to be 6. When Blue paper turns red in acid, then the pH is less than 7.

Source: RRB NTPC 2021 CBT 1 Previous Year Paper (3 Feb) — ixambee compilation with answer key · reliable-secondary

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