- Arrangement of Elements
- Group I Properties
- (a) decreasing melting point
- (b) increasing density
- (c) increasing reactivity
- Group VII Properties
- (a) increasing density
- (b) decreasing reactivity
- (a) chlorine, a pale yellow-green gas
- (b) bromine, a red-brown liquid
- (c) iodine, a grey-black solid
- Transition Elements
- (a) have high densities
- (b) have high melting points
- (c) form coloured compounds
- (d) often act as catalysts as elements and in compounds
- Noble Gases