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Question
The half-life of the radioisotope 158Eu is 0.77 h. How much time is required for a 160.0-g sample of 158Eu to decay to 1.29 g?A) 6.0 h
B) 4.0 h
C) 3.0 h
D) 2.3 h
E) 5.4 h
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:
Nitrosyl chloride is produced from the reaction of nitrogen monoxide and chlorine:2NO(g) + Cl2(g) → 2NOCl(g)The following initial rates at a given temperature were obtained for the concentrations listed below. ExperimentInitial Rate (mol·L-1·h-1)[NO]0(mol·L-1)[Cl2]0(mol·L-1)12.210.250.25219.890.750.2536.630.250.75From the data, what is the experimental rate law?A) Rate = k[Cl2]B) Rate = k[NO]C) Rate = k[NO][Cl2]2D) Rate = k[NO]2[Cl2]E) Rate = k[NO][Cl2]1/2
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 _____.
A) increase by a factor of 2.
B) remain constant.
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