WorksheetsReversible and Irreversible Reactions and Chemical Equilibrium
Total questions: 25
Worksheet time: 25mins
For the reaction...
SO2(g) + O2(g) <−> SO3(g)
If the concentration of SO2(g) is increased, the equilibrium of the reaction will ___________.
shift to the left
shift to the right
not shift
At what time does the reaction reach equilibrium?
t1
t2
t3
t4
A double sided arrow (↔), indicates that a reaction is:
Reversible
Irreversible
Not reactive
At what time (in seconds) is equilibrium established?
0 seconds
1 second
5 seconds
10 seconds
Which of the following statements correctly describes any chemical reaction that has reached equilibrium?
The reaction is now irreversible.
The rates of the forward and reverse reactions are equal.
Both forward and reverse reactions have halted.
The concentrations of products and reactants are equal.
What are the two factors to look for when determining if the reaction is at equilibrium?
Forward reaction rate is faster than the reverse and concentrations are equal
Forward and reverse reaction rates are equal and concentration is constant
Forward and revers reaction rates are equal and concentration is equal
Forward reaction rate is faster than the reverse and concentration is equal
Calculate Kc for the reaction HI(g) —> H2(g) + I2(g) given that the concentrations of each species at equilibrium are as follows: [HI] = 0.85 mol/L, [I2] = 0.60 mol/L, [H2] = 0.27mol/L.
0.19
0.22
4.5
5.25
160
When the forward and reverse reactions are occurring at the same rate, the reaction is said to be at:
Chemical equilibrium
Chemical reaction
Chemical constant
Chemical peace
TRUE or FALSE:
"At equilibrium, the CONCENTRATIONS of reactants and products are EQUAL"
True
False
Given the Kc for a forward reaction, how can you find Kc for the reverse reaction?
Divide Kc by 1
Divide 1 by Kc
Square Kc
Take the square root of Kc
A very high value for K indicates that
reactants are favored.
products are favored.
equilibrium is reached slowly.
equilibrium has been reached
TRUE or FALSE:
"At equilibrium, the CONCENTRATIONS of products STAY the SAME"
True
False
For any reaction at chemical equilibrium, the concentrations of products and reactants
are equal.
change
remain unchanged
decrease
Why is equilibrium called a dynamic state?
Chemists try to convert as much reactants as possible into products.
The reactions at equilibrium continue to take place once equilibrium is established.
The products of a forward reaction are favored, so equilibrium lies to the right.
All chemical reactions are considered to be reversible under suitable conditions.
An exothermic reaction is allowed to reach equilibrium. If heat energy is then removed, the equilibrium will shift
toward the middle
toward the reactant side
toward the product side
TRUE or FALSE:
"At equilibrium, the RATES of the forward and reverse reactions are EQUAL"
True
False
When the rate of the forward reaction is equal to the rate of backward reaction, the system is said to be in
Chemical Equilibrium
Chemical Balance
Stoichiometry
Chemical Reaction
Le Chaltelier's Principle states that if a chemical system at equilibrium is stressed,
the system will adjust to increase the stress
the system will adjust to reduce the stress
the system will not adjust
SO2(g) + O2(g) <−> SO3(g)
If the equilibrium shifts to the right, the concentration of O2(g) will ___________.
For the reaction...
heat + N2(g) + O2(g) <−> 2NO(g)
If the heat is removed to the chemical system, the equilibrium will _______.
shift to the left
shift to the right
not shift
For the reaction...
N2 (g) + 3 H2 (g) <−> 2 NH3 (g)
If the pressure in the system is increased, the reaction will __________________.
shift to the left
shift to the right
not shift
Which of the following best describes a reversible reaction?
A) A reaction that proceeds in one direction only
B) A reaction that can proceed in both forward and reverse directions
C) A reaction that stops once equilibrium is reached
D) A reaction that only occurs under high pressure
In a closed system, what happens to the concentrations of reactants and products at chemical equilibrium?
A) They become equal
B) They fluctuate continuously
C) They remain constant
D) They decrease to zero
Consider the reaction: @@ ext{N}_2(g) + 3 ext{H}_2(g) ightleftharpoons 2 ext{NH}_3(g)@@. If the pressure is increased, what will happen to the equilibrium position?
A) Shift to the left
B) Shift to the right
C) No change
D) The reaction will stop
Which of the following is an example of an irreversible reaction?
A) Combustion of gasoline
B) Dissolution of salt in water
C) Melting of ice
D) Formation of a salt from an acid-base reaction
