Le Chatelier's Principle

At what time (in seconds) is equilibrium established?

• 0 seconds
• 1 second
• 7 seconds
• 10 seconds

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

Tags

NGSS.HS-PS1-6

When writing an endothermic reaction, heat energy is stated as

• product
• catalyst
• reactant

Tags

NGSS.HS-PS1-4

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

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-6

Which of the following is NOT true at equilibrium?

• The forward and reverse reactions proceed at the same rate.
• The concentrations of reactants and products do not change.
• The concentration of the reactants is equal to the concentration of the products.
• The forward and reverse reactions continue to occur.

Tags

NGSS.HS-PS1-6

For the reaction...
SO_2(g) + O_2(g) <−>  SO_3(g)
If the concentration of SO_2(g)  is increased, the equilibrium of the reaction will ___________.

• shift to the left
• shift to the right
• not shift

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-6

For the reaction...
SO_2(g) + O_2(g) <−>  SO_3(g)
If the equilibrium shifts to the right, the concentration of O_2(g) will ___________.

• increase
• decrease
• remain the same

Tags

NGSS.HS-PS1-6

For the reaction...
heat +  N_2(g)  +  O_2(g)  <−>  2NO_(g)
If  O_2(g) is removed, the  concentration of N₂ will _______.

• increase
• decrease
• remain the same
• double

A +  B <--> C + D   ΔH= 151kJ
Is this reaction endothermic or exothermic?  How do you know?

• endothermic; heat is absorbed
• endothermic; heat is released
• exothermic; heat is absorbed
• exothermic; heat is released

A +  B <--> C + D   ΔH= 151kJ
Rewrite the above equation with energy as a reactant or product:

• A +  B <--> C + D + energy
• A +  B + energy <--> C + D