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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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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