The half-life time for a 1st order decomposition of a substance dissolved in CCl4 is 2.5 hours at 30°C. The amount of substance left after 10 hours if the initial weight of the substance is 160g is
Correct answer: B. 10g
- A. 5g
- B. 10g
- C. 15g
- D. 20g
Explanation
No. of half life periods = Total time/Time of one half life period = 10/2.5 = 4 Now we know that the quantity left after 'n' half-life periods= (½)n × Initial quantity= (½)4 × 160= 160/2x2x2x2= 10 gm.
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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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