Laboratory Quiz: Distillation and Reactions

What is the main principle behind distillation?

• Separation of substances based on solubility

• Separation of substances based on boiling points

• Separation of substances using filtration

• Separation of substances using density differences

Why is methylene blue added to the water in the distillation experiment?

• To act as a catalyst

• To help detect impurities in the distilled water

• To improve boiling efficiency

• To neutralize acids in the solution

In the preparation of 0.04M HNO3, what is the primary purpose of shaking the flask upside down?

• To speed up the reaction

• To mix the solution evenly

• To remove dissolved gases

• To evaporate excess water

What factor directly affects the rate of a chemical reaction?

• The volume of reactants

• The presence of a catalyst

• The shape of the reaction container

• The color of the reactants

In the factors affecting reaction rates experiment, which observation indicates that a reaction has occurred?

• A decrease in temperature

• A change in color or formation of a gas

• An increase in the solution's volume

• No change in the solution's properties

Which of the following would increase the rate of a reaction?

• Decreasing reactant concentration

• Lowering the temperature

• Grinding a solid reactant into smaller pieces

• Using a less reactive metal

When a catalyst is added to a reaction, it:

• Lowers the activation energy

• Increases the concentration of reactants

• Raises the boiling point of the solution

• Changes the final products of the reaction

In the surface area experiment, which form of eggshell reacted faster with HCl?

• Whole eggshell

• Chopped eggshell

• Pulverized eggshell

• The reaction rate was the same for all

According to Le Chatelier's Principle, when the pressure increases, the equilibrium will shift:

• Toward the side with fewer gas molecules

• Toward the side with more gas molecules

• Toward the reactants

• It will remain unchanged

What gas is collected in the syringe in the pressure experiment?

• Oxygen (O₂)

• Carbon dioxide (CO₂)

• Nitrogen dioxide (NO₂)

• Hydrogen (H₂)