Question

Question 7.42 The pH of a sample of vinegar is 3.76. Calculate the concentration of hydrogen ion in it.

Class XI Equilibrium Page 228

Answer 1

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Answer 2

pH = -log[H⁺]
here, given pH = 3.76
so,  3.76 = -log[H⁺]
log[H⁺] = -3.76
before taking antilog we have to use concept of characteristics and mantissa concept e.g., add -1 in characteristics (-3) and +1 in mantissa (0.76)
  e.g., -3.76 convert in $\overline{4}.24$
then, [H⁺] = antilog($\overline{4}.24$)
                = 1.738 × 10⁻⁴ M