Ionic, covalent (and metalic) bonding

Question 1

Ions

Answer 1

Ions are formed by the loss (form positive ions) or gain (form negative ions) of electrons by atoms.
Ionic bonding occurs between a metal wanting to lose electron(s) and a nonmetal wanting to gain
electron(s).

Question 2

What are the charges of all the Groups?

Answer 2

G1 = +1
G2 = +2
G3 = +3
G5= -3
G6 = -2
G7 = -1

Question 3

Bonding

Answer 3

Electrostatic forces of attraction between oppositely charged ions

Question 4

Ionic bonding

Answer 4

METAL and NON-METAL
- Occurs between a metal wanting to lose electron(s) and a non-metal wanting to gain electron(s)
- Electrons are transferred from the metal to the non-metal and how many each atom gains or loses

Question 5

Physical properties of ionic bonding

Answer 5

• High melting points – oppositely charged ions strongly attract and it takes a lot of energy to break this attraction
• Conduct when molten or aqueous – ions free to move and carry the charge. When solid the ions are not free to move and so cannot conduct

Question 6

Covalent bonding

Answer 6

NON-METALS
- Formed between atoms by the sharing of a pair of electrons
- Strong electrostatic forces of attraction between bonding/shared pair of electrons and both nuclei of the two atoms.
- Generally do not conduct electricity as do not possess delocalised electrons which are free to move.

Question 7

Simple molecular covalent

Answer 7

• Gases of liquids, or solids with low melting and boiling points
• As they have low boiling points they have weak intermolecular forces of attraction which require very little
  heat energy to break.
• Their melting and boiling points increase with increasing relative molecular mass as they contain more electrons and therefore have stronger intermolecular forces which require more energy to break
• They do not conduct electricity as they possess no delocalised electrons to carry
  the charge and have no overall electric charge.

Question 8

Graphite (covalent structure)

Answer 8

• Each carbon atom is bonded to three others. It, therefore, has one free delocalised electron for every carbon atom. These delocalised electrons can move through the structure and conduct electricity.
• It has a high melting point as it is a giant covalent structure with very strong bonds.
• It possesses weak intermolecular forces of attraction between the hexagonal layers which mean they can slide over each other and be used as a lubricant.

Question 9

Diamond (covalent structure)

Answer 9

• Giant covalent structure/lattice with each carbon atom strongly bonded to four other carbon atoms. As it possesses strong covalent bonds throughout its structure it has a high melting point as it takes a lot of heat energy to break them
• It is used as a cutting material on drills
• Each carbon atom is bonded to four others so no free delocalised electrons and therefore does not conduct electricity like graphite