acids, bases + salts

salts are made when an acid reacts with a base, carbonate or metal
1. the name of the salt formed depends on the metal in the base and the acid used
  1. e.g. salts made using hydrochloric acid are called chlorides
acids
1. substances with a pH of less than 7
2. the more strongly acidic the solution, the lower its pH number
3. turns blue litmus paper red
4. turn universal indicator paper red if they are strongly acidic, or orange or yellow if they are weakly acidic
bases
1. substances that can react with acids + neutralise them to make a salt + water
2. usually metal oxides or metal hydroxides
  1. e.g. copper oxide and sodium hydroxide are bases
alkalis
1. bases than dissolve in water
2. copper oxide is not an alkali because it DOES NOT dissolve in water
3. sodium hydroxide is an alkali because it DOES dissolve in water
4. pH of more than 7
  1. the stronger the alkali, the higher the pH number
5. turn red litmus paper blue
6. turn universal indicator paper dark blue or purple
neutral solutions
1. have a pH of 7
2. do not change the colour of litmus paper
3. turn universal indicator green
4. e.g. water

Resource summary

	Created by charlotte_lucy_9 over 11 years ago