Physical changes in water are most often caused by _______.

• chemical reactions

• oxidation

• temperature

• combustion

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which term describes the substance that forms when two or more types of atoms join?

• compound

• element

• composite

• mixture

Tags

NGSS.MS-PS1-1

A cube of sodium chloride—which is table salt—is soluble in water.

This statement is an example of what type of change and what action.

• physical; corrode

• chemical; dissolve

• chemical; sink

• physical; dissolve

Which shows one example of a physical change and then one example of a chemical change?

• boiling water and burning gasoline

• dissolving sugar and grinding pepper

• melting butter and mixing flour with salt

• roasting meat and freezing leftovers

Tags

NGSS.MS-PS1-4

NGSS.MS-PS1-5

-Which is a compound?

• sodium

• sugar

• nitrogen

• air

Tags

NGSS.MS-PS1-1

This table provides information about some group 1 elements. Which is the best estimate of the melting point of Rubidium (Rb)?

• 25 C

• 40 C

• 75 C

• 184 C

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Two different liquids are poured together in an open container. Bubbles begin to form. After the bubbling stops, it is determined that the total weight of the two liquids is less than before they were poured together. Which best describes this observation?

• Some of the atoms during the reaction escaped into the air.

• Some of the atoms during the reaction were destroyed.

• Some of the atoms during the reaction became heavier.

• Some of the atoms during the reaction changed to a different kind of atom.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

This is a chemical reaction for the decomposition of carbonic acid into water and carbon dioxide.

H2CO3 → H2O + CO2

How does the reaction support the Law of Conservation of Mass?

• Several molecules of water are produced.

• The mass of carbon atoms is reduced during the reaction.

• The mass of the atoms in the reactant equals the mass of the atoms in the products.

• The mass of hydrogen atoms is the only thing that remains the same before and after the reaction.

Tags

NGSS.MS-PS1-5

Which is classified as an element?

• carbon dioxide

• iron

• vinegar

• water

Which best describes the sequence of the elements in Period 5 of the periodic table?

• highly reactive gases, relatively nonreactive metals, metalloids, very nonreactive gases, nonreactive nonmetals

• highly reactive metals, relatively nonreactive metals, metalloids, reactive nonmetals, nonreactive gases

• nonreactive gases, metalloids, nonreactive metals, highly reactive metals, highly reactive gases

• nonreactive gases, nonreactive metals, highly reactive metals, metalloids, reactive nonmetals, reactive gases