C2.5 Ionic Compounds

Question 1

How are ionic bonds formed?

Answer 1

Atoms of most elements have incomplete outer shells of electrons.they can lose or gain electrons during chemical reactions. Groups of atoms may become ions if they lose or gain electrons

Question 2

What happens when atoms of different elements combine?

Answer 2

They form compounds by the formation of new chemical bonds

Question 3

What is an ion

Answer 3

An atom with a positive or negative charge

Question 4

Describe the formation of sodium ions Na+

Answer 4

When sodium atoms lose electrons to form positively charged ions called cations. Metal atoms lose outermost shells when they form ions. For elements in group 1 and 2, number of outer electrons lost is proportional to their group number

Question 5

Describe the formation of chloride ions CI-

Answer 5

When non metal atoms such as chloride gain electrons to form negatively charged ions called anions. When non metal atoms form anions endings are always -ide. They gain electrons to complete their outermost shell when they form ions.
Electrons that non metal atoms gain from group 6/7 are 8 - their group number . In this case a chlorine atom in group 7 loses one electron to complete its outermost shell.