Background: Chemical equilibrium was studied by French chemist Henri Le Châtelier (1850-1936), and his description of how a system at equilibrium responds to a change in conditions has become known as Le Châtelier’s principle . This principle states that when a chemical system is at equilibrium and is disturbed by a stress, the system will respond by attempting to counteract that stress until a new equilibrium is established. Stresses to a chemical system include changes in the concentrations of reactants or products, changes in the temperature of the system, or changes in the pressure of the system. We will discuss each of these stresses separately. In each case, the change to the equilibrium position will cause either the forward or reverse reaction to be favored over the opposite process. When the forward reaction is favored, the concentrations of the products increase, and the concentrations of the reactants decrease. When the reverse reaction is favored, the concentrations of the products decrease, and the concentrations of the reactants increase.

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: In which case the system would try to counteract, case E or case T?
Answer: case T

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: In which case the system would not try to counteract, case E or case T?
Answer: case E

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: In which case the products concentration would increase, case A or case B?
Answer: case A

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: In which case the products concentration would decrease, case A or case B?
Answer: case B

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: Would the products concentration increase or decrease in case A than in case B?
Answer: increase

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: Would the products concentration increase or decrease in case B than in case A?
Answer: decrease

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: In which case the reactants concentration would increase, case A or case B?
Answer: case B

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: In which case the reactants concentration would decrease, case A or case B?
Answer: case A

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: Would the reactants concentration increase or decrease in case A than in case B?
Answer: decrease

Situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored.

Question: Would the reactants concentration increase or decrease in case B than in case A?
Answer: increase

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Which test saw higher concentrations of the products, test C or test D?
Answer: test C

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Which test saw lower concentrations of the products, test C or test D?
Answer: test D

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Would test C see higher or lower concentrations of the products than test D?
Answer: higher

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Would test D see higher or lower concentrations of the products than test C?
Answer: lower

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Which test saw higher concentration of the reactants, test C or test D?
Answer: test D

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Which test saw lower concentration of the reactants, test C or test D?
Answer: test C

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Would test C see higher or lower concentration of the reactants than test D?
Answer: lower

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: Would test D see higher or lower concentration of the reactants than test C?
Answer: higher

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: In which test Le Chatelier's principle had been applied, test A or test B?
Answer: test B

Situation: John was trying to reenact Le Chatelier's principle. To that end, he conducted four tests, test A, test B, test C, and test D. In test A, he didn't input any stress to a chemical system in equilibrium. But In test B, he put some stress to the same system. In test C, he observed a forward reaction, but in test D, he observed a reverse reaction.

Question: In which test Le Chatelier's principle had not been applied, test A or test B?
Answer: test A