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Question
Which of the following will cause the calculated molar mass of a compound determined by the freezing-point-depression method to be greater than the true molar mass?A) When the solute was added, some was spilled on the lab bench.
B) Water gets into the solvent after the freezing point of the pure solvent is determined.
C) Some of the solute molecules break apart.
D) The mass of solvent is smaller than that determined from the weighing.
E) all of the above
Answer
This answer is hidden. It contains 1 characters.
Related questions
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E) Based on the atomic mass, only 7Li occurs naturally.
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Q:
Suppose atom 1 has the same number of protons as atom 2, and atom 2 has the same number of neutrons as atom 3. Atom 1 does not have the same number of neutrons as atom 3. Which of the following statements is true?
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Q:
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Q:
If the Thomson model of the atom had been correct, Rutherford would have observed
A) alpha particles bouncing off the foil.
B) alpha particles going through the foil with little or no deflection.
C) alpha particles greatly deflected by the metal foil.
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Q:
A subatomic particle is
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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)
Q:
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Q:
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Q:
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Q:
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Q:
Which of the following corresponds to the correct equation for the half-life of a first-order reaction?A) B) C) D) E)
Q:
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Q:
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Q:
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Q:
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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