To ensure you find the right gift (and quickly!), we broke down these best Valentine's Day gift ideas by category, including home, kitchen, tech, beauty, and more. All these picks are sure to ...

Look at a couple of ionic compounds eg sodium chloride, magnesium oxide and copper sulfate and thier properties - link back to activity in topic3.

Looking at trends - not that not all can be explained unless we use a more complex model of the atom. Link to the page with the orbital model Links to periodic table Born Haber cycle - may be give one ...