ProbSet9_solutions(2) - Chapter 15: Concepts in Chemical...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 15: Concepts in Chemical Kinetics True/False and Multiple Choice (7) 1) What is the order of an elementary reaction: A+2B -> 1C a) 2 b) 7 c) 4 d) 3 e) 8 2) The addition of a catalyst increases the rate of the reaction but not the equilibrium constant True /False 3) For a reaction with a larger Δ G, compared to a reaction with a smaller Δ G: a) The reaction larger Δ G is always the faster reaction b) The reaction larger Δ G is always the slower reaction c) The two rates are equal d) It is impossible to decide which reaction is faster 4) For elementary reactions of 0 th and 2 nd order with a rate constant of 1 (with appropriate units), the 2 nd order reaction half life is a shorter period of time. True/ False 5) The most basic step used to describe a reaction process is: a) transition state b) elementary reaction c) unimolecular reaction d) steady state e) equilibrium rate 6) The probability of a bimolecular reaction occurring is related to the rate of collisions between the two species of molecules True /False 7) After excitation, the light emitted by a fluorescent molecule drops exponentially with time.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
True /False Fill in the blank (5) 1) The symbol “‡” is used to represent the ______________ of the reaction ( transition state ) 2) The rate law gives the relationship between the rate of a reaction and the ________ of the chemical species involved in the reaction. ( concentrations ) 3) The rate constant for a _____ order elementary reaction is s -1 M -1 ( second ) 4) The rate of product formation at the end of a pathway is determined by the rate of the ______ step ( slowest) 5) Catalysts can work by changing the reaction mechanism, ________, or _________. (decreasing the activation energy, increasing the pre-exponential factor/(increasing the rate of collisions with favourable orientation)) Quantitative/Essay Problems (12) 1) How do the kinetics of hydrolysis of ATP to ADP and phosphate by water make it a good energy reservoir for the cell? Answer: Hydrolysis of ATP yields a large amount of energy (~30kJ/mol) but the forward rate is very slow. Unless an enzyme catalyst is present, water does not spontaneously react frequently with ATP. Due to this slow rate of hydrolysis, very little energy is lost unless a catalyst initiates the reaction. 2) Below is a two-dimensional energy vs. reaction coordinate diagram for the reaction AB+C -> A+BC. Circle the approximate area that represents the transition state and justify your answer. Answer:
Background image of page 2
The transition state is the highest point of energy on the trajectory between reactants and products. 3) **Iodine-123 is important for medical imaging studies and follows first-order decay kinetics. A 15 µ g sample of I-123 has decayed to 7.5 µ g after 13 hours. After how much time will it decay to only 1.5 µ g? Answer:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 19

ProbSet9_solutions(2) - Chapter 15: Concepts in Chemical...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online