| A | B |
|---|
| fluorine | most reactive of the halogens |
| iodine | least reactive of the halogens |
| diatomic | pairs of atoms |
| green gas | chlorine |
| orange liquid | bromine |
| inert | not reactive |
| party balloons | helium |
| neon | advertising signs |
| most dense noble gas | xenon |
| potassium | bursts into a lilac flame when it reacts with water |
| hydrogen | gas formed when sodium reacts with water |
| lithium | least reactive alkali metal |
| 2.8.1 | sodium |
| endothermic | heat taken in iduring a reaction |
| exothermic | heat given out in a reaction |
| -ide | containing two elements |
| -ate | containing oxygen and other elements |
| coloured compounds | transition metals |
| green-blue flame test | copper |
| yellow-red flame test | calcium |
