C2 - Formation Of Ions

Question 1

What are ions?

Answer 1

Ions are charged particles - they can be single atoms or groups of atoms

Single atom eg - Cl-
Group of atom eg - No3-

Question 2

Why do atoms lose or gain electrons?

Answer 2

Atoms want a full outer shell like noble gases (also called a “stable electronic structure). Atoms with full outer shells are very stable.

Question 3

What ions do metals form?

Answer 3

When metals form ions, they lose electrons from their outer shell to form positive ions (cations)

Question 4

What ions do non-metals form?

Answer 4

When non-metals form ions, they gain electrons into their outer shell to form negative ions (anions)

Question 5

FACT : NO NEED TO REMEMBER

Answer 5

The number of electrons lost or gained is the same as the charge on the ion.

E.g. If 2 electrons are lost the charge is 2+. If 3 electrons are gained the charge is 3-

Question 6

In what group do element most readily form ions?

Answer 6

The elements that most readily form ions are those in Groups 1, 2, 6 and 7

Question 7

What ions do group 1 and 2 elements form?

Answer 7

Group 1 and 2 elements are metals and they lose electrons to form positive ions (cations)

Question 8

What ions do group 6 and 7 form?

Answer 8

Group 6 and 7 elements are non-metals. They gain electrons to form negative ions (anions)

Question 9

FACT : NO NEED TO REMEMBER

Answer 9

Elements in the same group all have the same number of outer electrons. So they have to lose to get the same number to get a full outer shell. And this means that they form ions with the same charges

Question 10

When sodium loses an ion what electronic structure is it similar to?

Answer 10

Neon

Question 11

When magnesium loses two ions what electronic structure is it similar to?

Answer 11

Neon

Question 12

When chlorine gains an ion what electronic structure is it similar to?

Answer 12

Argon

Question 13

When oxygen gains two ions what electronic structure is it similar to?

Answer 13

Neon