Aims

Class work Structures and Properties

Ionic CompoundsLO’s• What are the properties of ionic

compounds?

Write it down!! Page 48© C Meyer

Chemistry Unit 2 Sections

Structures Structures and bonding and properties How

much? 2 of 7

© C Meyer

All• Know the main properties of ionic

compounds

Most/Some• Relate their properties to their

structure

Aims

• Metals (left side) lose electrons to get a full shell• Non metals (right side) gain electrons to get a full shell• + and - ions that form strongly attract each other

• What are ionic bonds? Use sodium chloride as an example

What have I learnt?

• What are ionic bonds? Use sodium chloride as an example (Na =11, Cl = 17)

What have I learnt?

m2

• What structure do ionic compounds have/what do they look like?

What have I learnt?

m1

+-+

-

- -

-+

+

+ -+-

+

-

-+ +

+-+

-

- -

-+

++ -

+-

+

-

-+ +

+ -+-

+

-

-+ +

+-+

-

- -

-+

+

Lots ofionic bonds

+ and –attract

strongly

Background - water, water everywhere• What is the formula for water?• What does a molecule look like?

What are the properties of ionic compounds?

O

HH

O H

H

Covalent bondsm3

• You will do a series of experiments

• For each experiment write a conclusion/say why the ionic compound has that property using your knowledge of ionic bonding

What are the properties of ionic compounds?

1. Observation – look at the crystals under a hand lens. What is structure, is it solid, liquid or gas? Why?

2. Scratch test – Take a needle. Try to scratch the surface CARE. Is the surface hard or soft? Why?

3. Melting point – Place a spatula full of the crystals in a boiling tube. Heat in the blue flame CARE. Do they have high or low melting points? Why?

4. Solubility – Take a small beaker, half filled with water. Add 2 spatulas full of crystals. What happens? Why?

SAFETY 18 mins

5. Conductivity – Take a small beaker. Put a layer of crystals on the bottom. Dip in the electrodes, does the lamp light? Why? Now add water CARE - Chlorine. Does the lamp light? Why?

Tidy UP!!!

• Stack items tidily• Clean up bench/floor• Sit down when finished

• List the main properties of ionic compounds and explain why they have those properties

Homework

1. ObservationWhat are the properties of ionic compounds?

• Solid, crystals – due to strong ionic bond. Particles close and hard to break apart

2. Scratch test• Hard, scratch resistant – strong ionic

attractive bonds3. Melting point• High melting point. Did not melt (easily)

– strong ionic attractive bonds m3

What are the properties of ionic compounds?4. Solubility• Easily dissolves – Water is not neutral,

has a charge so can attract ions in lattice and pull them apart

m1

m1

What are the properties of ionic compounds?5. Conductivity• Solid does not conduct. When solution

conducts – in solution ions are free to move. They carry a charge so go to the opposite electrode.

• Ions would also conduct when at very high temperature and molten

What are the properties of ionic compounds?

The End