Understanding Atoms and Molecules

What are atoms considered to be in relation to all matter?

• The largest units

• The basic building blocks

• Complex compounds

• Energy sources

What three subatomic particles are atoms made up of?

• Protons, electrons, and ions

• Neutrons, protons, and molecules

• Protons, neutrons, and electrons

• Electrons, ions, and compounds

What is the smallest unit of matter that still keeps the basic properties of an element?

• A molecule

• A compound

• An atom

• A proton

How are molecules formed?

• When atoms break apart

• When two or more atoms bond together

• When elements are heated

• When electrons are removed from an atom

Why do atoms bond together to form molecules?

• To become less stable

• To create new elements

• To become more stable

• To increase their size

How can atoms be thought of in relation to molecules?

• As the final products of molecules

• As the energy source for molecules

• As the building blocks used to make molecules

• As the waste products of molecules

What is a single oxygen (O) represented as in chemistry?

• A molecule

• A compound

• An atom

• An ion

What is the chemical formula for the oxygen that humans breathe?

• O

• O3

• O2

• H2O

How many hydrogen atoms and oxygen atoms are in a water molecule (H2O)?

• One hydrogen, two oxygen

• Two hydrogen, one oxygen

• Two hydrogen, two oxygen

• One hydrogen, one oxygen

Which of the following is an example of an atom?

• CO2

• H2O

• Fe

• CCl4