Unit 4 test

Which of the following statements is not a requirement for a reaction to occur between reacting particles?

• reacting substances must collide

• reacting substances must collide with the correct orientation.

• reacting substances must be identical to react.

• reacting substances must collide with sufficient energy.

The diagram above is showing unsuccessful reaction. Which of the following is not a probable reason for an unsuccessful reaction?

• Reactants are moving too slowly

• Reactants are not facing each other at the right angle

• Reactants do not have sufficient energy

• Reactants are in correct orientation.

Which of the following are necessary for successful collisions to occur?

I ​Favorable collision geometry

​II ​Sufficient Kinetic energy

​III ​Large amount of heat

• I only

• I and II only

• II and III only

• I, II, and III

Collision theory states that

• All collisions lead to chemical reactions

• Most collisions lead to chemical reactions

• Very few reactions involve particle collisions

• Effective collisions lead to chemical reactions

When a lit match is touched to the wick of a candle, the candle begins to burn. When the match is removed, the candle continues to burn. In this reaction, the match

• Behaves as a catalyst

• Supplies activation energy

• ​Is part of the rate-determining step

• Lowers the activation energy barrier

When you walk through a crowded hallway at school, you are more likely to bump into another person. To which of the following factors that affect rate of reaction is this analogy referring?

• catalyst

• . surface area

• temperature

• concentration

Which of the following will lower the rate of reaction?

• adding an enzyme to the reaction

• decreasing the temperature from 40˚C to 10˚C

• breaking a chunk of calcium up into smaller pieces

• increasing the amount of solute dissolved in a solution

A student adds iron filings to a copper(II) chloride solution at room temperature. A balanced equation for the reaction that occurs is shown below.

Fe(s) + CuCl2 (aq) = FeCl2 (aq) + Cu(s)

Which of the following changes would most likely increase the reaction rate?

• using larger pieces of iron

• performing the reaction in an ice bath

• increasing the volume of the CuCl2 solution

• increasing the concentration of the CuCl2 solution

Which of the following are true about how temperature affects the rate of reaction?

• I and II only

• I and III only

• II and III only

• I, II and III

Increasing which of the following will increase the frequency of collisions?

• I and II only

• I and III only

• II and III only

• I, II, and III