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Question
A 4.50-mg sample of a newly discovered radioactive nuclide was analyzed and found to contain only 3.25 mg after a period of 31.9 h. What is the half-life of the nuclide?A) 77.3 h
B) 67.9 h
C) 72.2 h
D) 12.8 h
E) 16.8 h
Answer
This answer is hidden. It contains 1 characters.
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Q:
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Q:
If a reaction is first-order with respect to a particular reactant, when the concentration of that reactant is increased by a factor of 2, the reaction rate will _____.
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Q:
For a certain first-order reaction with the general form aA → products, the rate is 0.32 M·s-1 when the concentration of the reactant is 0.29M. What is the rate constant for this reaction?A) 0.26 s-1B) 1.1 s-1C) 0.32 s-1D) 3.1 s-1E) 3.8 s-1