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Question
Which of the following statements is/are CORRECT according to valence bond theory?1/ The overlap between an s orbital and a p orbital is called a pi-bond.
2/ The overlap of two s orbitals in H2 is called a sigma bond.
3/ HF is formed from the overlap of a hydrogen 1s orbital with a fluorine 2p orbital.
A.1 only
B.2 only
C.3 only
D.2 and 3
E.1, 2, and 3
Answer
This answer is hidden. It contains 2 characters.
Related questions
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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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A.
B.
C.
D.
E.
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Q:
If the reaction quotient, Q, is equal to K in a gas phase reaction, then
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Q:
For the reaction 2A + B C, the rate law is
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For the reaction A B, the rate law is
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B.
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What is the overall order of the reaction below
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Q:
Which statement concerning relative rates of reaction is correct for the chemical equation given below?
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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.
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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]