When you boil water, are you causing a chemical change or a physical change?

• Physical

• Chemical

Identify the following as an atom, element, or molecule: PH₃

• atom

• element

• molecule

What four things are necessary for photosynthesis? Select all four that apply.

• oxygen

• catalyst

• sunlight

• water

• carbon dioxide

A student reports on an atom that has 11 protons, 10 neutrons, and 10 electrons. What is wrong with the student’s report?

• Neutrons should be the total of electrons and protons

• The electrons and protons must be equal in an atom

Two atoms have the same number of neutrons but different numbers of protons. Do they belong to the same element?

• sometimes

• yes

• depends

• no

How many total atoms are in one molecule of C₂₂H₄₄O?

• 65

• 67

• 66

• 64