Chemistry 2 Lesson 2.1 Ionic Compounds AQA Additional Science

Aims Class work Structures and Properties Ionic Compounds LO’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? m Lots of ionic 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 H H O H H Covalent bonds m3

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.Observation What 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 bonds 3.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

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