Chemistry Unit Review

Which is most likely to be a mixture?

• substance formed when one atom combines with another atom of the same element

• substance formed when one atom combines with an atom of another element

• solution formed when one substance chemically combines with another

• solution formed when one substance dissolves in another

Water (H₂O) and table salt (NaCl) can be combined to form salt water. How can this combination be classified?

• as a compound because the water (H₂O) and table salt (NaCl) are chemically combined

• as a compound because the water (H₂O) and table salt (NaCl) form a new pure substance

• as a mixture because the water (H₂O) can be evaporated and physically separated from the table salt (NaCl)

How are atoms combined in a mixture?

• chemically combined and cannot be separated

• physically combined and can be separated

• chemically combined and can be separated

In which state of matter will the atoms of an element be tightly packed together?

• gas

• liquid

• solid

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which is a mixture?

• H₂O

• salad

• table salt

Which choice best describes the properties of potassium (K), based on its position on the periodic table of elements?

• A nonreactive metal

• A highly reactive metal

• A nonreactive nonmetal

• A highly reactive nonmetal

Which statement best explains how periods on the periodic table are organized?

• increasing atomic number from left to right

• increasing number of neutrons from left to right

• decreasing number of electrons from left to right

• decreasing atomic mass number from left to right

Which pair of elements has the most similar properties?

• Li and B

• I and Ca

• K and He

• N and P

Sodium reacts with water. Which element is most likely to have a similar effect to sodium if it is exposed to water?

• carbon

• oxygen

• lithium

Where on the periodic table are you most likely to find elements that do not react with other elements?

• group 1

• group 17

• group 18