Answer

Type 1 – this type allows a set amount of solution to be dispensed from the zero mark at the top of the pipette. For example, if you wanted to dispense 5ml, then you would fill the pipette up to the zero mark at the top and dispense down to the 5ml graduation on the pipette. Zero is near the top of this type, with the numbers increasing as you go down the tube.

 Type 2 – with this type, you fill the pipette up to the graduation of the amount you want to dispense (e.g. 5ml), then dispense all of the solution until the pipette is empty. Zero is effectively the bottom tip of this type, with the numbers increasing as you go up the tube.

 Generally, type 2 pipettes are slightly more popular than type 1 pipettes, in schools.

 Regarding which is most suitable for GCSE use, it depends on whether or not you only need to dispense a set amount of solution once for an experiment (e.g. dispense 2ml of solution once only) or whether you need to dispense several amounts for an experiment (e.g. you might have a 10ml pipette and want to dispense 1ml amounts several times). Type 2 is probably more fool-proof in this respect as you can’t over-shoot the mark with these because you dispense the set amount completely – but it does depend on how you anticipate these being used.