Structure Of Atoms And Ions

Question 1

What is the structure of an atom in terms of positions, relative masses and relative charges of sub-atomic particles?

Answer 1

There is a nucleus, protons, electrons, neutrons, shells
Proton charge : +1
Electrons charge : -1
Neutrons charge : 0
Protons relative mass : 1
Electrons relative mass : negligible 1/ 1836
Neutons relative mass : 1

Question 2

What is an atomic number and mass number?

Answer 2

Atomic number : number of protons
Mass number = atomic number + number of neutrons
Number of protons and electrons is always the same

Question 3

How are ions formed and what are they?

Answer 3

Ions are charged atoms and are formed when the outer shell of an atom becomes full.
Positive ions are formed when electrons are lost and negative ions are formed when electrons are added.

Question 4

How do you know the charges of ions by referring to the periodic table?

Answer 4

Groups 1 - 3 the number of ions increases (starts with +1 ion and goes to +2 to +3)
Group 4 are already ions
Groups 5 - 7 the number of ions decreases (starts with -3 ions to -2 to -1)