Chemistry · Rate of a chemical reaction, factors affecting the rate of reactions: concentration, temperature, pressure and catalyst

A reaction is catalysed by ion. In presence of HA, rate constant is min and in p

A reaction is catalysed by \( \boldsymbol{H}^{+} \) ion. In presence of HA, rate constant is \( 2 \times \) \( 10^{-3} \) min \( ^{-1} \) and in presence of HB rate constant is \( 1 \times 10^{-3} \) min \( ^{-1} \), HA and HB both being strong acids, we may conclude that: This question has multiple correct options

  • A. equilibrium constant is 2
  • B. HA is stronger acid than HB.
  • C. relative acidic strength of HA and HB is 2.
  • D. HA is weaker acid than HB and relative strength is 0.5

Step-by-step solution

The reaction is catalyzed by H⁺, so the rate constant is proportional to [H⁺]. Assuming equal concentrations of HA and HB (both strong acids), their dissociation should yield equal [H⁺] if they were equally strong. However, the rate constant for HA is twice that for HB, indicating that HA provides a higher [H⁺] concentration. Thus, HA is a stronger acid than HB.
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