Atomic Structure + Periodic Table

Question 1

What is an atom?

Answer 1

The smallest unit of matter that retains the properties of an element.

Question 2

What is a proton?

Answer 2

Positively charged subatomic particles in the nucleus (+1).

Question 3

What is a neutron?

Answer 3

Neutral subatomic particle in the nucleus (0).

Question 4

What is an electron?

Answer 4

Negatively charged subatomic particle outside the nucleus (-1).

Question 5

What is the nucleus?

Answer 5

The center of an atom; contains protons and neutrons.

Question 6

What is atomic number?

Answer 6

The number of protons in an atom; identifies the element.

Question 7

What is mass number?

Answer 7

The number of protons plus the number of neutrons.

Question 8

What is a group in the periodic table?

Answer 8

A column on the periodic table; elements in the same group have the same number of valence electrons.

Question 9

What is a period in the periodic table?

Answer 9

A row on the periodic table.

Question 10

What are valence electrons?

Answer 10

Electrons in the outermost energy shell; they determine reactivity.