Y9 Recap

Question 1

Atomic Structure

Answer 1

Protons +
Neutrons ~
Electrons -

Protons and neutrons are found in the nucleus, relatively heavy

Electrons orbit the nucleus. Very light

Question 2

Roles of Protons Neutrons and Electrons

Answer 2

What determines the type of atom?
The number of protons

What determines the mass of an atom?
The number of protons and neutrons

What determines the net charge of an atom?
The ratio of protons to electrons

What determines the stability of an atom?
The ratio of neutrons and protons

Question 3

Isotopes

Answer 3

Atoms of the same element, same number of protons that have a different et number of neutrons.

The mass number on periodic table is not a whole number because it is a calculated average of all known isotopes of an element

Question 4

Ions

Answer 4

Neutral atom have a 0 charge, equal number of protons and electrons

Positive ions are called cations
Negative ions are called anions

Question 5

Valence shells

Answer 5

First can hold 2 electrons
Second 8
Third 8
Fourth 18

Atoms have a valence shell, full outer shell are unreactive

If gain=anion
If lose=cation

Metals are likely to lose electrons, cations
Non metals are likely to gain, anions