MISA - Maryland Integrated Science Assessment Properties of Chemical Reactions Questions and Answers

Question 1

A student mixes two clear, colorless liquids in a beaker. They observe the formation of a white solid and notice the beaker feels warm to the touch. Which statement best explains these observations?

Accepted Answer

A chemical reaction occurred, indicated by the formation of a precipitate and a change in temperature.

Answer

A physical change occurred, causing one liquid to freeze.

Answer

The liquids were contaminated, resulting in a precipitate.

Answer

The beaker absorbed heat from the room, causing a solid to form.

Question 2

In a closed system, 22 grams of reactant X are completely reacted with 8 grams of reactant Y. According to the Law of Conservation of Mass, what is the expected total mass of the products?

Accepted Answer

30 grams.

Answer

Less than 30 grams if a gas is produced.

Answer

More than 30 grams if the reaction is exothermic.

Answer

14 grams.

Question 3

A student wants to increase the rate of reaction between a solid lump of calcium carbonate and a hydrochloric acid solution. Which of the following actions would be LEAST effective at increasing the reaction rate?

Accepted Answer

Decreasing the concentration of the hydrochloric acid solution.

Answer

Crushing the lump of calcium carbonate into a powder.

Answer

Gently warming the hydrochloric acid solution.

Answer

Stirring the mixture continuously.

Question 4

The chemical equation for the combustion of methane is: CH₄ + 2 O₂ → CO₂ + 2 H₂O. In this reaction, which of the following are the reactants?

Accepted Answer

CH₄ and O₂

Answer

CO₂ and H₂O

Answer

CH₄ and CO₂

Answer

O₂ and H₂O

Question 5

An instant cold pack is activated by breaking an inner pouch, allowing two substances to mix. The pack quickly becomes very cold. This is an example of what type of process?

Accepted Answer

An endothermic reaction

Answer

An exothermic reaction

Answer

A combustion reaction

Answer

A physical change

Question 6

The chemical reaction 2 H₂O₂ → 2 H₂O + O₂ shows hydrogen peroxide changing into water and oxygen gas. How is this type of reaction best classified?

Accepted Answer

Decomposition

Answer

Synthesis

Answer

Single-replacement

Answer

Double-replacement