Changes in Chemical Reactions

Front

A solid, yellow substance formed when Mr. Simon poured two colorless liquids together at room temperature. Which statement best explains why this demonstrates a chemical reaction?

Back

The yellow substance is a solid at room temperature.

Front

The following are examples of physical properties except ____: ability to dissolve in water, density, shape

Back

ability to react with oxygen

Front

A characteristic of matter that allows it to change to something new is a ____.

Back

chemical property

Front

What evidence is shown when zinc metal is added to hydrochloric acid, resulting in the flask feeling warmer and the sample becoming smaller?

Back

a chemical change and an exothermic reaction

Front

Why is iron’s tendency to rust not a physical property?

Back

A new substance with new properties forms when iron rusts.

Front

Which statement explains the law of conservation of mass? Options: Every reaction creates an equal amount of mass related to the amount of energy required for the reaction., Substances cannot be created or destroyed in a reaction., The total amount of mass is equal to the volume of both chemicals in the reaction., The total mass before a chemical reaction is the same as the total mass after the reaction.

Back

The total mass before a chemical reaction is the same as the total mass after the reaction.

Front

When 5 g of solid zinc is placed into a beaker that holds 15 g of hydrochloric acid solution, bubbles of hydrogen form. The mass of the contents of the beaker after the reaction is less than 20 g. Which best explains the difference in mass?

Back

The lower mass is a result of the hydrogen gas leaving the beaker.

Front

Which statement best describes the two demonstrations?

Back

Demonstration 1 showed a chemical change because a new gaseous substance was formed, and demonstration 2 showed a physical change because liquid water became water vapor.

Front

Answer the question below
Options: A, B, C, D

Back

D

Front

Answer the question below
Options: A, B, C, D

Back

D