Lesson 5.

Question 1

What is the name of the bottom number for each element and what is its symbol?

Answer 1

That is the atomic number, and its symbol is “Z.”

Question 2

What is the name of the top number for each element and what is its symbol?

Answer 2

That is the atomic mass, and its symbol is “A.”

Question 3

What does the atomic mass show us?

Answer 3

The number of protons and neutrons.

Question 4

What does the atomic number tell us?

Answer 4

It tells us the number of protons. It also indirectly tells you how many electrons there as, as the number of electrons and protons are always the same.

Question 5

What else can you call the atomic mass?

Answer 5

The mass number.

Question 6

TRUE OR FALSE:
There are different numbers of electrons and protons.

Answer 6

False. There is the same number of electrons and protons.

Question 7

Define the term “isotopes.”

Answer 7

Isotopes of an element are atoms with the same number of protons and electrons, but different numbers of neutrons.

Question 8

Complete the sentence:
Isotopes have the same ………. number but different ……. number.

Answer 8

1) Atomic.
2) Mass.

Question 9

What does the chemical and physical properties of an isotope depend on?

Answer 9

All the isotopes of an element have the same number of electrons, so they would have identical chemical properties. However, the different numbers of neutrons may affect their physical properties.

Question 10

What are ions?

Answer 10

lons are charged particles. They are formed when atoms, or groups of atoms, lose or gain electrons.