Half-life of an element is 5 days. If we have 50,000 of its atoms, then how many atoms would be left after 10 days ?
Correct answer: D. None of these
- A. 15000
- B. 25000
- C. 50000
- D. None of these
Explanation
The half-life of the element is 5 days. After each half-life, the number of atoms is reduced by half* Initial amount: 50,000 atoms* After 5 days (one half-life): 50, 000/2 = 25.000 atoms* After another 5 days (second half-life, totaling 10 days): 25. 000 2 = 12,500 atomsTherefore after 10 days, 12,500 atoms would be left.
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About Reaction Kinetics
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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