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Question
Iodine-131, which is used to treat thyroid cancer, has a half-life of 8.04 days. How much time is required for 84% of the isotope to decay?A) 21 days
B) 7 days
C) 41 days
D) 53 days
E) 2 days
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Which of the following atomic symbols represents an isotope of ?
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Q:
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E) number of isotopes.
Q:
If the Thomson model of the atom had been correct, Rutherford would have observed
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B) alpha particles going through the foil with little or no deflection.
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Q:
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B) CO(g) + H2O(g) CO2(g) + H2(g)
C) CO(g) + 3H2(g) CH4(g) + H2O(g)
D) CaO(s) + CO2(g) CaCO3(s)
E) HBr(g) H2(g) + Br2(l)
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For the reaction 2NO(g) + O2(g) 2NO2(g) at 750ºC, what is the relationship between Kc and Kp?A) Kc= KpB) Kc= Kp x (RT)-1C) Kc= Kp= 1.0D) Kc= Kp x (RT)E) Kc= Kp x (RT)1
Q:
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Q:
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Which of the following corresponds to the correct equation for the half-life of a first-order reaction?A) B) C) D) E)
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The nuclide 96Nb decays by a first-order process with a rate constant of 2.96 x 10-2 h-1. How long will it take for 82.0% of the initial amount of 96Nb to be consumed?A) 33.8 hB) 57.9 hC) 27.7 hD) 6.70 hE) 6.08 h
Q:
The reaction between selenous acid and the iodide ion in acid solution isH2SeO3(aq) + 6I-(aq) + 4H+(aq) → Se(s) + 2I3-(aq) + 3H2O(l)The data in the following table were measured at 0C. Experiment[H2SeO3]0(M)[H+]0(M)[I-]0(M)Initial Rate [mol/(L·s)]11.00 x 10-42.00 x 10-23.00 x 10-25.30 x 10-722.00 x 10-42.00 x 10-23.00 x 10-21.06 x 10-633.00 x 10-44.00 x 10-23.00 x 10-26.36 x 10-643.00 x 10-48.00 x 10-23.00 x 10-22.54 x 10-553.00 x 10-48.00 x 10-26.00 x 10-22.04 x 10-462.00 x 10-42.00 x 10-26.00 x 10-28.48 x 10-6Tripling the initial concentration of H2SeO3while holding the initial concentrations of H+ and I- constant increases the rate of the reaction by a factor ofA) 8.B) 4.C) 3.D) 2.E) 1.
Q:
The reaction between selenous acid and the iodide ion in acid solution isH2SeO3(aq) + 6I-(aq) + 4H+(aq) → Se(s) + 2I3-(aq) + 3H2O(l)The data in the following table were measured at 0C. Experiment[H2SeO3]0(M)[H+]0(M)[I"]0(M)Initial Rate [mol/(L·s)]11.00 x 10-42.00 x 10-23.00 x 10-25.30 x 10-722.00 x 10-42.00 x 10-23.00 x 10-21.06 x 10-633.00 x 10-44.00 x 10-23.00 x 10-26.36 x 10-643.00 x 10-48.00 x 10-23.00 x 10-22.54 x 10-553.00 x 10-48.00 x 10-26.00 x 10-22.04 x 10-462.00 x 10-42.00 x 10-26.00 x 10-28.48 x 10-6What is the rate constant for this reaction?A) 1.5 x 104L5/(mol5·s)B) 1.5 x 1010L5/(mol5·s)C) 4.9 x 105L5/(mol5·s)D) 294 L5/(mol5·s)E) 8.8 L5/(mol5·s)
Q:
For the reaction A + B + C → products, the following initial-rate data were obtained. [A]0(mol/L)[B]0(mol/L)[C]0(mol/L)Initial Rate (mol/(L·s))0.400.400.200.01600.200.400.400.00800.600.100.200.00150.200.100.200.00050.200.200.400.0020What are the reaction orders with respect to A, B, and C, respectively?A) 0, 1, 1B) 1, 2, 1C) 1, 1, 1D) 1, 2, 0E) 0, 2, 1
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