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