ECU CHEM 1120 Exam 3 Review – Practice Test & Chemistry Exam Preparation
1 MOLE - ANS ✔✔6.02x10^23
Exothermic - ANS ✔✔Gives off heat; (-ΔH); Enthalpy "heat"
Endothermic - ANS ✔✔absorbs heat; (ΔH); Enthalpy "heat"
Endergonic - ANS ✔✔Non-spontaneuos; (ΔG)
Exergonic - ANS ✔✔Spontaneous; (-ΔG)
Entropy - ANS ✔✔Disorder/randomness/freedom of motion (ΔS)
Entropy equation - ANS ✔✔ΔG= ΔH-TΔS
What entropy is said to be the best reactions? - ANS ✔✔+ΔS AND -ΔH (Spontaneous)
Le Chatelier's Principle - ANS ✔✔Reactions at equilibrium will stay at equilibrium, but if a stress
is applied to a reaction at equilibrium, the rate of the forward or reverse reaction will increase
to relieve the stress.
A+B (Reactants) : Add/increase - ANS ✔✔Shift right; forward reaction favored
A+B (Reactants): Remove/decrease - ANS ✔✔Shift left/reverse reaction favored
C+D (Products): Add/increase - ANS ✔✔Shift left; reverse reaction favored
, C+D (Products): Remove/decrease - ANS ✔✔Shift right; forward reaction favored
Limiting Reagent - ANS ✔✔Reactant with the fewest number of moles
ΔH - ANS ✔✔Amount of heat given off (or absorbed)
SO3 + H20 = H2SO4 + 21 Kcal - ANS ✔✔Exothermic reaction(gives off heat); ΔH= -21 Kcal/mol
N2+O2+ 43 Kcal =2 NO - ANS ✔✔Endothermic reaction(heat absorbed)
What happens when ΔG is negative? - ANS ✔✔Reactants turn into products
Chemical Equilibrium - ANS ✔✔Rate of the forward reaction = rate of the reverse reaction
Equilibrium constant (Keq) - ANS ✔✔Keq= [Products]
[Reactants]
4 assumptions about gases - ANS ✔✔1. Gas molecules have no attraction to each other
2. Theres a lot of empty space between gas molecules
3. The speed with which gas molecules move is proportional to the temp (K)
4. Gas molecules collide with the walls of their containers generating pressure.
Pressure - ANS ✔✔1.00 atm= 760 mm Hg= 14.7 psi
Endothermic - ANS ✔✔+ΔH and +ΔS
1 MOLE - ANS ✔✔6.02x10^23
Exothermic - ANS ✔✔Gives off heat; (-ΔH); Enthalpy "heat"
Endothermic - ANS ✔✔absorbs heat; (ΔH); Enthalpy "heat"
Endergonic - ANS ✔✔Non-spontaneuos; (ΔG)
Exergonic - ANS ✔✔Spontaneous; (-ΔG)
Entropy - ANS ✔✔Disorder/randomness/freedom of motion (ΔS)
Entropy equation - ANS ✔✔ΔG= ΔH-TΔS
What entropy is said to be the best reactions? - ANS ✔✔+ΔS AND -ΔH (Spontaneous)
Le Chatelier's Principle - ANS ✔✔Reactions at equilibrium will stay at equilibrium, but if a stress
is applied to a reaction at equilibrium, the rate of the forward or reverse reaction will increase
to relieve the stress.
A+B (Reactants) : Add/increase - ANS ✔✔Shift right; forward reaction favored
A+B (Reactants): Remove/decrease - ANS ✔✔Shift left/reverse reaction favored
C+D (Products): Add/increase - ANS ✔✔Shift left; reverse reaction favored
, C+D (Products): Remove/decrease - ANS ✔✔Shift right; forward reaction favored
Limiting Reagent - ANS ✔✔Reactant with the fewest number of moles
ΔH - ANS ✔✔Amount of heat given off (or absorbed)
SO3 + H20 = H2SO4 + 21 Kcal - ANS ✔✔Exothermic reaction(gives off heat); ΔH= -21 Kcal/mol
N2+O2+ 43 Kcal =2 NO - ANS ✔✔Endothermic reaction(heat absorbed)
What happens when ΔG is negative? - ANS ✔✔Reactants turn into products
Chemical Equilibrium - ANS ✔✔Rate of the forward reaction = rate of the reverse reaction
Equilibrium constant (Keq) - ANS ✔✔Keq= [Products]
[Reactants]
4 assumptions about gases - ANS ✔✔1. Gas molecules have no attraction to each other
2. Theres a lot of empty space between gas molecules
3. The speed with which gas molecules move is proportional to the temp (K)
4. Gas molecules collide with the walls of their containers generating pressure.
Pressure - ANS ✔✔1.00 atm= 760 mm Hg= 14.7 psi
Endothermic - ANS ✔✔+ΔH and +ΔS
