Matter

When a person chews, saliva from the mouth mixes with starches in food. These starches begin to turn into sugars. Changing starches into sugars is BEST described as

• a phase change

• a cellular change

• a physical change

• a chemical change

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Some power plants produce energy by burning coal. In these power plants, the heat from burning coal is used to boil water. Which statement BEST describes the changes that occur when burning coal and boiling water?

• Burning coal and boiling water are both physical changes.

• Burning coal and boiling water are both chemical changes.

• Burning coal is a chemical change, and boiling water is a physical change.

• Burning coal is a physical change, and boiling water is a chemical change.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Which statement BEST describes the formation of rust?

• Rust results from a physical mixing of iron with water.

• Rust forms from a chemical breakdown of old metal.

• Rust results from a chemical reaction between iron and water.

• Rust forms from a physical change when wind blows against metal.

Tags

NGSS.MS-PS1-2

Which of the following is an example of a pure substance?

• Nickel

• air

• peanuts

• blood

Tags

NGSS.MS-PS1-4

Which of the following examples can be identified as a physical property?

• magnetism

• oxidation (rust)

• flammability

• pH

Which is an example of a chemical reaction?

• Water evaporates into air

• Vinegar added to baking soda forms a gas

• Sugar dissolves in water

• Corn kernels are crushed to form flour

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

When frozen carbon dioxide is heated, it changes directly into a gas. Which statement BEST indicates that a physical change has taken place?

• Heat caused an increase in gas production.

• Heat caused a new substance to form.

• Heat caused a decrease in energy.

• Heat caused a change in state.

Tags

NGSS.MS-PS1-4

In physical changes, substances might change in ________ but not in _______

• appearance, composition

• volume, state of matter

• texture, color

• weight, mass

Tags

NGSS.MS-PS1-4

One molecule of carbon dioxide (CO₂) combines with one molecule of water (H₂O) to make one molecule of carbonic acid. According to the Law of Conservation of Mass, how many atoms of carbon should be in the carbonic acid?

• 1

• 2

• 3

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

What is the importance of a closed container in a chemical reaction?

• to observe the mass before and after the reaction occurs

• to keep any materials from interfering with the reaction

• to observe the loss of mass after the reaction occurs

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5