4.3 The Atom

Open Ended

What is the Learning Goal?

Multiple Choice

The idea of atoms did not become scientific theory until

• 1708.

• 1808.

• 1908.

• 2008.

Open Ended

Who developed an atomic theory that proposed that atoms were responsible for the combinations of elements found in compounds?

Multiple Choice

Atoms are too small to see.

• This statement is FALSE.

• This statement is TRUE.

Match

Match the following

• two positive charges

• two negative charges

• positive and a negative charge

Repel

Repel

Attract

• Repel

• Repel

• Attract

Multiple Choice

In 1897, J.J. Thomson discovered that cathode rays were streams of negatively charged particles called

• protons.

• neutrons.

• electrons.

• quarks.

Match

Match the following

• proton

• electron

• neutron

Positive charge

Negative charge

No charge

• Positive charge

• Negative charge

• No charge

Multiple Choice

Chemists use the __ to indicate the mass of an atom.

• Da

• amu

Multiple Choice

Mass of the atom are due to the ___ in the nucleus.

• electrons and protons

• protons and neutrons

• neutrons and electrons

• just electrons

• just protons

Match

Match the following

• 1+

• 0

• 1-

• nucleus

• outside nucleus

p+

n

e-

Proton

electron

• p+

• n

• e-

• Proton

• electron