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Question
Which of the following statements is/are CORRECT?1/ The atomic radii of transition metals decrease initially, then increase as one moves from left to right across a period of the periodic table.
2/ The atomic radii of the d-block elements in the 5th and 6th periods in each group are almost identical.
3/ The densities of the 6th period transition metals are greater than those of either the 4th or 5th period transition metals.
A.1 only
B.2 only
C.3 only
D.1 and 2
E.1, 2, and 3
Answer
This answer is hidden. It contains 2 characters.
Related questions
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Q:
An aqueous solution with a pH of 10.60 is diluted from 1.0 L to 2.0 L. What is the pH of the diluted solution?
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B.9.60
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An aqueous solution with a pH of 2.00 is diluted from 1.0 L to 3.0 L. What is the pH of the diluted solution?
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Q:
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Q:
Assume that the following endothermic chemical reaction is at equilibrium.
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2/ Decreasing the temperature will cause the reaction to proceed in the forward direction, increasing the equilibrium concentration of CO(g).
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N2(g) + 3 H2(g) 2 NH3(g) K2
H2(g) + 1/2 O2(g) H2O(g) K3
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A.
B.
C.
D.
E.
Q:
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Q:
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Q:
If the reaction quotient, Q, is equal to K in a gas phase reaction, then
A.the chemical system has reached equilibrium.
B.the temperature must be increased for the reaction to proceed in the forward direction.
C.the reaction will proceed in the forward direction until equilibrium is established.
D.the reaction will proceed in the backward direction until equilibrium is established.
E.the reaction will proceed in the direction that increases the number of gas phase particles.
Q:
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Q:
For the reaction 2A + B C, the rate law is
.
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2/ adding a catalyst
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A.1 only
B.2 only
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Q:
For the reaction A B, the rate law is
.
What are the units of the rate constant where time is measured in seconds?
A.
B.
C.
D.
E.
Q:
What is the overall order of the reaction below
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if it proceeds via the following rate expression? A.zero-order
B.first-order
C.second-order
D.third-order
E.fourth-order
Q:
Which statement concerning relative rates of reaction is correct for the chemical equation given below?
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A.The rate of disappearance of CH3OH is equal to the rate of disapperance of O2.
B.The rate of disappearance of CH3OH is two times the rate of appearance of H2O.
C.The rate of disappearance of CH3OH is half the rate of appearance of CO2.
D.The rate of appearance of H2O is two times the rate of appearance of CO2.
E.The rate of appearance of H2O is four times the rate of disappearance of CH3OH.
Q:
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Q:
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Q:
The rate constant at 366 K for a first-order reaction is 7.7 10-3 s-1 and the activation energy is 15.9 kJ/mol. What is the value of the frequency factor, A, in the Arrhenius equation? (R = 8.314 J/Kmol)A.0.0047 s-1B.0.70 s-1C.0.93 s-1D.1.1 s-1E.1.4 s-1
Q:
Calculate the activation energy, Ea, forN2O5(g) 2 NO2(g) + 1/2 O2(g)given k (at 45.0 C) = 5.79 10-4 s-1 and k (at 60.0 C) = 3.83 10-3 s-1. (R = 8.314 J/Kmol)A.0.256 kJ/molB.2.83 kJ/molC.31.1 kJ/molD.111 kJ/molE.389 kJ/mol
Q:
What is the half-life of a first-order reaction if it takes 4.4 10-2 seconds for the concentration to decrease from 0.50 M to 0.20 M?A.2.5 10-2 sB.3.3 10-2 sC.1.6 sD.21 sE.27 s
Q:
Hydrogen peroxide decomposes into water and oxygen in a first-order process.
H2O2(aq) H2O() + 1/2 O2(g)
At 20.0 C, the half-life for the reaction is 3.92 104 seconds. If the initial concentration of hydrogen peroxide is 0.52 M, what is the concentration after 7.00 days?
A.1.2 10-5 M
B.0.034 M
C.0.074 M
D.0.22 M
E.0.52 M
Q:
A student analyzed a first-order reaction and obtained the graph below. Unfortunately, the student forgot to label the axes. What are the correct labels for the x and y axes? A.x axis = time, y axis = ln[A]
B.x axis = ln[time], y axis = [A]
C.x axis = ln[time], y axis = [A]
D.x axis = time, y axis = 1/[A]
E.x axis = 1/time, y axis = 1/[A]