The half-life of N2O5 at 0°C is 24 minutes. How long will it take for a sample of N2O5 to decay to 25% of its original concentration?
Correct answer: D. 48 minutes
- A. 24 minutes
- B. 72 minutes
- C. 120 minutes
- D. 48 minutes
Explanation
After one half-life, the concentration of N2O5 will be reduced to 50% of its original concentration. After two half-lives, it will be reduced to 25% of its original concentration.Given that the half-life is 24 minutes, we need to calculate the time it takes for two half-lives to pass.Two half-lives would be equal to 2 * 24 minutes = 48 minutes.Therefore, it will take 48 minutes for the sample of N2O5 to decay to 25% of its original concentration.Among the given options, the closest value is Option D: 48 minutes.
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Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
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