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Question
An unknown element, X, reacts with oxygen to form two oxides with the general formula X2O3 and X2O5. The pure element is strongly paramagnetic, and the oxides are amphoteric. Which of the following elements could be represented by X?A) Sc
B) Na
C) Bi
D) S
E) Sb
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:
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 _____.
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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