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Question
The average atomic mass of Eu is 151.96 amu. There are only two naturally occurring isotopes of europium, 151Eu with a mass of 151.0 amu and 153Eu with a mass of 153.0 amu. The natural abundance of the 131Eu isotope must be approximatelyA) 60%.
B) 20%.
C) 50%.
D) 80%.
E) 40%.
Answer
This answer is hidden. It contains 1 characters.
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Q:
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Q:
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Q:
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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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C) decrease by a factor of .
D) decrease by a factor of .
E) increase by a factor of 4.
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