Chapter summary
Experimental Chemistry, at a glance
Select apparatus, separate mixtures and judge what measurements actually show.
SEC G2 Science K223 / K225 (2027)
Quick revision
Revisit the essentials, then return to an explanation when you need it.
| Term | Definition to write |
|---|---|
| Pure substance | A single substance that is not mixed with anything else. It melts and boils at fixed (sharp) temperatures. |
| Mixture | Two or more substances that are not chemically combined. They can be separated by physical methods. |
| Residue and filtrate | The residue is the solid left on the filter paper; the filtrate is the liquid that passes through it. |
| Difference | Method |
|---|---|
| Insoluble solid in liquid | Filtration |
| Soluble solid wanted | Crystallisation or suitable evaporation |
| Solvent wanted | Simple distillation |
| Miscible liquids with different boiling points | Fractional distillation |
| Different movement with solvent and paper | Chromatography |
Choose measurements with suitable precision. Distinguish observation from inference. A clear liquid is not automatically pure.
Quick recall
Which apparatus measures exactly 25.0 cm3 of a solution for a titration?