Chemical Properties

A scientist is examining an unknown solid. Which procedure would most likely help determine a chemical property of the substance?

• heating it to find the temperature at which it melts

• exposing it to a flame to see if it catches on fire

• hitting it with a hammer to determine if it breaks or bends

• placing it in water to find out whether or not it dissolves

Which characteristic of a substance is considered a chemical property?

• its boiling point

• its reactivity

• its density

• its conductivity

Which statement best describes chemical properties of matter?

• Chemical properties, such as density, must be observed when a substance is in its natural state at room temperature and normal atmospheric pressure.

• Chemical properties, such as reactivity, must be observed when a substance is in its natural state at room temperature and normal atmospheric pressure.

• Chemical properties, such as combustibility, are generally observed as the identity of a substance changes and one or more new substances form.

• Chemical properties, such as boiling point, are generally observed as the identity of a substance changes and one or more new substances form.

Which use of iron is due to its chemical properties?

• producing colored sparks in fireworks

• changing from liquid to gas at 2,862°C

• conducting electricity and heat

• changing from solid to liquid if heated to 1,538°C

Which statement best describes what happens during a chemical change?

• Both the identity and the properties of a substance change.

• Some properties of a substance change, but its identity remains the same.

• The chemical properties of a substance change, but its physical properties remain the same.

• The physical properties of a substance change, but its chemical properties remain the same.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In a demo, Zn is mixed with HCl; bubbles form and a balloon inflates. What most likely occurred?

• The Zn and HCl both retained their identity.

• Either Zn or HCl, but not both, retained its identity.

• Evaporation of one of the substances occurred.

• One or more new substances formed.

Tags

NGSS.MS-PS1-2

Henry dissolved salt in water, then left it in the sun; only salt remained and mass decreased. He concluded a physical and chemical change occurred. Which statement is correct?

• He is correct… dissolving is physical, evaporating is chemical; formation of a solid shows chemical change.

• He is correct… evaporation is physical, dissolving is chemical; mass change shows chemical change.

• He is incorrect. Dissolving and evaporation are both physical changes; the reappearance of salt shows a reversible physical change, not a chemical change.

• He is incorrect. Dissolving and evaporation are both chemical changes…

Tags

NGSS.MS-PS1-2

Cash mixes two clear liquids; bubbles form and a white solid precipitates. If he heats it, what is most likely true?

• A physical change occurred; heating will dissolve the white solid back to the original liquids.

• A physical change occurred; heating won’t dissolve the white solid.

• A chemical change occurred; heating will dissolve the white solid back to the original liquids.

• A chemical change occurred; even if heated, the white solid will remain.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

NGSS.MS-PS1-5

What is the outcome of all chemical changes when two substances are combined?

• A new substance forms with identical properties.

• The two substances release an odor.

• The two substances change color.

• A new substance forms with different properties.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which laboratory activity involves a chemical change?

• leaving a copper penny in vinegar until it turns green

• boiling saltwater until only solid salt remains

• extracting iron filings from sand with a magnet

• crushing a rock with a hammer to extract minerals

Tags

NGSS.MS-PS1-2