Elements and Compounds Review

An unknown silvery solid has a constant boiling point and high density. It can chemically separate into other substances but cannot physically separate into other substances. The unknown substance can be classified as _____.

• element

• compound

• homogeneous mixture

• heterogenous mixture

A student studies a pure substance made up of one type of atom. It is a gas that cannot chemically or physically separate into other substances. The unknown substance can be classified as _____.

• element

• compound

• homogeneous mixture

• heterogenous mixture

Which of the following chemical symbols best represents an element?

• CO

• O₂

• CO₂

• H₂0

Which of the following chemical formulas best represents a compound?

• Co

• O₂

• CO₂

• He

A student needs a sample of lead during a lab. Which of the containers below should the student remove the sample from?

• Fe

• L

• Le

• Pb

A student needs a sample of salt during a lab. Which of the containers below should the student remove the sample from?

• Sa

• Na

• NaCl

• NA

Which of the following is a compound?

• Hs (hassium)

• CO (carbon monoxide)

• Cl (chlorine)

• Na (sodium)

Which of the following is an element?

• Br₂ (bromine)

• NH₃ (ammonia)

• SiO₂ (quartz)

• H₂O (water)

What do you call one or two letters used to represent the element’s name where the first letter is always capitalized?

• chemical symbol

• chemical formula

What is a pure substance that is made up of 2 or more different atoms that are chemically bonded?

• element

• compound

• homogeneous mixture

• heterogenous mixture