Question: How does a catalyst influence a chemical equilibrium?
Answer Options: A. It changes the position of the equilibrium
B. It speeds up the rate of the back reaction only
C. It speeds up the rate of the forward and back reactions
D. It speeds up the rate of the forward reaction only
Answer: C. It speeds up the rate of the forward and back reactions
Question: The combustion of octane is an exothermic reaction. Which statement is true for an exothermic reaction?
Answer Options: A. It consumes heat because the reactants have a higher energy than the products.
B. It releases heat because the reactants have a higher energy than the products
C. It releases heat because the reactants have a lower energy than the products
D. It consumes heat because the reactants have a lower energy than the products
Answer: B. It releases heat because the reactants have a higher energy than the products
Question: Which is the least stable type of reactive intermediate?
Answer Options: A. Methane carbocation
B. Tertiary carbocation
C. Secondary carbocation
D. Primary carbocation
Answer: A. Methane carbocation
Question: We have transferred 25 mL of sulfuric acid sample into a volumetric flask. Why do we use a volumetric flask?
Answer Options: A. It doesn’t require careful dexterity
B. To obtain accurate and precise volume
C. To be able to heat it in later stage
D. It’s the only glassware that can handle acid dilution
Answer: B. To obtain accurate and precise volume
Question: Why do we not just calibrate the gas thermometer at absolute zero?
Answer Options: A. Condensation of water vapor in the lab would raise the temperature.
B. Waiting for equilibrium at absolute zero would take much more time than is available.
C. Measuring absolute zero requires liquid deuterium for coolant which is expensive.
D. Absolute zero cannot practically be produced in any lab setting.
Answer: D. Absolute zero cannot practically be produced in any lab setting.
Question: The unit of enthalpy is joules. What is joules a measure of?
Answer Options: A. Temperature
B. Sugar content
C. Atomic Mass
D. Energy
Answer: D. Energy
Question: What is entropy?
Answer Options: A. Entropy determines whether a reaction is favorable or not.
B. Entropy is a measure of the disorder of a system.
C. Entropy is a measure of the heat of a system.
D. Entropy is a measure of the total energy of a system.
Answer: B. Entropy is a measure of the disorder of a system.
Question: We learned that pH is related to hydrogen ions concentration [H+]. What will happen if lower the hydrogen ion concentration?
Answer Options: A. The pH will be the same
B. The pH will be lower
C. Hydrogen ion concentration of a solution cannot be changed
D. The pH will be higher
Answer: D. The pH will be higher
Question: Which statement about a chemical equilibrium is correct?
Answer Options: A. The forward reaction is faster than the reverse reaction
B. Forward and reverse reactions happen at equal rates
C. The reverse reaction is faster than the forward reaction
D. No reactions take place at equilibrium
Answer: B. Forward and reverse reactions happen at equal rates
Question: Which statement about a chemical equilibrium is correct?
Answer Options: A. Forward and reverse reactions happen at equal rates
B. The reverse reaction is faster than the forward reaction
C. No reactions take place at equilibrium
D. The forward reaction is faster than the reverse reaction
Answer: A. Forward and reverse reactions happen at equal rates
Question: What do you have to do if there is an unexpected violent chemical reaction in a bottle?
Answer Options: A. Add water
B. Evacuate
C. Add baking soda for neutralization
D. Close the lid of the bottle
Answer: B. Evacuate
Question: Which of the following parameters affect the zero temperature?
Answer Options: A. The type of gas.
B. Neither the type of gas nor the initial pressure.
C. Both the type of gas and the initial pressure.
D. The initial pressure.
Answer: B. Neither the type of gas nor the initial pressure.
Question: As the temperature of the gas is increased the molecules in the gas move faster, the pressure on the side walls of a container is also increased. Why?
Answer Options: A. Due to the increased kinetic energy which results in higher impacts to the walls.
B. The molecules in the gas change phases and cling to the sides of the container.
C. The fewer impacts among the molecules result in fewer collisions to the walls.
D. Steam or water vapor enters the container and increases the pressure.
Answer: A. Due to the increased kinetic energy which results in higher impacts to the walls.
Question: Which role does the double bond play in the electrophilic addition reaction mechanism?
Answer Options: A. Electrophile
B. Nucleophile
C. Spectator
D. None
Answer: B. Nucleophile
Question: The completion of acid-base titration is represented by end-point and equivalence point. What is end-point?
Answer Options: A. The theoretical completion of the reaction
B. Point where the number of moles of bases is equals to the number of moles of acid
C. Point where the indicator changes color
D. Point where the neutralization reaction is complete
Answer: C. Point where the indicator changes color
Question: What do you have to do before leaving the lab, to make sure you don’t carry traces of chemicals outside?
Answer Options: A. Turn off the main power
B. Tell your supervisor
C. Wash your hands and then remove your lab coat
D. Take off your lab coat and wash your hands
Answer: D. Take off your lab coat and wash your hands
Question: What is the pH of a 0.01 M solution of carbonic acid?
Answer Options: A. 2
B. 4.18
C. 0.01
D. 1
Answer: B. 4.18
Question: What should we do to reduce the risk when working with high concentrated acid and base?
Answer Options: A. Dilute the acid
B. Never work with it
C. Work in large volume
D. Neutralize it
Answer: A. Dilute the acid
Question: If equal volumes of a strong base and a weaker acid are mixed together, what would you expect the pH of the resulting salt to be?
Answer Options: A. pH < 7, because there will be fewer [OH-] than [H+]
B. pH = 7, because an acid and base neutralization always makes a neutral
C. pH > 7, because there will be fewer [H+] than [OH-]
D. pH = 0, because the pH has been used up
Answer: C. pH > 7, because there will be fewer [H+] than [OH-]