1. Metal Oxides + Acid
D. Crowley, 2007

2. Metal Oxides + Acid
To know what happens when an acid reacts with a metal oxide

3. Chemical Reactions
Today you are going to undertake an experiment with acid + metal oxide
Using your sheet, list three things we may expect to see if a chemical reaction has taken place…
Temperature change
Fizzing
pH change
Colour change
Gas given off

4. Reactions So far, we have seen lots of reactions
Using the sheet, see if you can note the correct answers
metal + oxygen → metal oxide
metal + water → metal (hydr)oxide + hydrogen
metal + acid → salt + hydrogen
Today we are going to look at metal oxides + acid…

5. Metal Oxides
Metal oxides are the compounds that form when a metal reacts with oxygen - they are all bases (alkali)
metal + oxygen  metal oxide
copper + oxygen  copper oxide
magnesium + oxygen  magnesium oxide
sodium + oxygen  ______ _____
iron + oxygen  ____ _____

6. Metal Oxides
Metal oxides are the compounds that form when a metal reacts with oxygen - they are all bases (alkali)
metal + oxygen  metal oxide
copper + oxygen  copper oxide
magnesium + oxygen  magnesium oxide
sodium + oxygen  sodium oxide
iron + oxygen  ____ _____

7. Metal Oxides
Metal oxides are the compounds that form when a metal reacts with oxygen - they are all bases (alkali)
metal + oxygen  metal oxide
copper + oxygen  copper oxide
magnesium + oxygen  magnesium oxide
sodium + oxygen  sodium oxide
iron + oxygen  iron oxide

8. Experiment
Today you are going to react a metal oxide with acid, forming a salt + water
The metal oxide we are going to use is copper oxide
Metal oxides are bases (alkali) - what do you think will happen when you add this to an acid?

9. Neutralisation Add small amounts of copper oxide in a beaker
Add 25cm3 sulphuric acid, and stir
Keep adding, until some un-reacted copper oxide remains at the bottom
Filter the solution, removing the un-reacted copper oxide
Transfer the filtrate to an evaporating basin
Heat gently, until about one third of the water has evaporated
Leave the solution to cool, and examine the crystals…

10. Neutralisation
As the metal oxide is a base, it has neutralised the acid, leaving a salt + water
Write down in your own words what the copper crystals looked like, followed by a word (and symbol) equation