After planning an investigation, the next step is to think about what equipment to use, and how to conduct the experiment safely.
If certain chemicals are going to be used, the potential hazards need to be identified to ensure that they’re used safely. This might affect the concentrations of solutions or the quantities used and even whether those substances are used at all. The hazards also need to influence the general running of the experiment and how the equipment is used.
The next step is to think about the most appropriate equipment to use. For example, the volume of a liquid could be measured using a beaker, a measuring cylinder or a burette. In different circumstances one of these might be safer or more accurate than others, which would affect the choice.
If you need to measure out 5 cm3 of liquid then a 10 cm3 measuring cylinder would give a more accurate volume then using a 100 cm3 measuring cylinder. Also, using balances that measure mass to the nearest 0.01 g will give a more accurate measurement then using ones that measure mass to the nearest gram.