Unit 12 Exam Review Flashcards
Energy that is available to do work is called:
Gibbs’ Free Energy
______ is defined as the number of atoms, ions, or molecules that react in a given time to form products:
reaction rate
What is the name of the minimum energy that colliding particles must have in order to react?:
activation energy
What is the arrangement of atoms at the peak of an energy barrier?:
activated complex
At equilibrium, what is the rate of production of reactants compared with the rate of production of products?:
the same
The rate of a chemical reaction normally ______ as reactant concentration increases:
increases
The amount of disorder in a system is measured by its _______:
Entropy
If a reaction has an equilibrium constant (Keq) just greater than 1, how do we interpret that information?:
Products are favoured
Which variable is NOT required to calculate the Gibbs free-energy change for a chemical reaction?:
A. Change in enthalpy
B. Change in entropy
C. Temperature in ºC
D. Temperature in KTemperature in ºC
What is the effect of adding more water to the following equilibrium reaction … CO2 + H2O H2CO3
Concentration of H2CO3 increases
In an endothermic reaction at equilibrium, what is the effect of raising the temperature?:
Shift to the products
What is the numerical value ( + or – ) of Gibbs free-energy for a spontaneous reaction?:
∆G is negative
At what stage of a reaction do atoms have the highest energy?:
At the transition stage (activated complex)
Which of the following systems has the highest entropy:
A. 10 mL of HCL at 50ºC
B. 10 mL of HCL at 100ºC
C. 10 mL of HCL at 75ºC
D. 10 mL of HCL at 10ºC10 mL of HCL at 100ºC
An elementary reaction converts reactants to products in ______:
a single step
Consider the reaction … N2(g) + 3H2(g) 2NH3(g) … What is the effect of decreasing the volume on the contained gases?:
Concentration of NH3 increases, concentration of H2 decreases
Spontaneous reactions always __________ free energy:
release
What physical state of nitrogen has the highest entropy?:
gas
What is another name for the catalysts in your body?:
Enzyme
In an equilibrium reaction with a Keq of 1 x 10^8 , the ________ are favoured:
products
In which of these systems is the entropy decreasing:
A. salt dissolving in water
B. a liquid cooling
C. heating a liquid
D. breaking apart a sugar cubea liquid cooling
In a two-step mechanism, how many elementary reactions occur?:
2
The Keq of a reaction is 4 x 10^-7 . At equilibrium, the ______ are favoured:
reactants
Another name for the activated complex is _______:
transition state
A catalyst works by:
decreasing the needed activation energy
