Which of the following statements about ethene, C2H4, is incorrect? ()
A. The H-C-H bond angles are approximately 109.5°.
B. All of the hydrogen atoms are in the same plane.
C. There is a total of five sigma bonds.
D. The carbon atoms are sp2 hybridized.
E. The H-C-H bond angles are approximately 120°.
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An increase in which of the following will occur if the reaction temperature is ()? I. Energy of activation II. Collision frequency III. Fraction of collisions with sufficient energy
A. I and II
B. I and III
C. II and III
D. I, II, and III
E. I
Which of the following correctly describes intermediates and/or transition states? ()
A. Transition states occur at minima on reaction coordinate diagrams.
Both transition states and intermediates occur at maxima on reaction coordinate diagrams.
C. An intermediate is always produced after the rate-determining step of a reaction mechanism.
D. Transition states have partially formed bonds whereas intermediates have fully formed bonds.
E. none of the above
An () in which of the following results in a () in the rate of the chemical reaction? ()
A. temperature
B. concentration
C. collision frequency
D. energy of activation
E. fraction of collisions with proper orientation
How many carbons are in the planar double-bond system of 3-methylcyclopentene? ()
A. 0
B. 1
C. 2
D. 3
E. 4
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