periodic table Flashcards
(7 cards)
1
Q
periodic table
A
arrangement of elements in periods and groups in order of increasing proton number
2
Q
group 1 trends down the group
A
- decreasing melting point
- increasing density
- increasing reactivity
3
Q
halogens
A
diatomic non-metals
4
Q
halogen trends down group
A
- increasing density
- decreasing reactivity
5
Q
halogens appearance at r.t.p
A
chlorine: pale yellow-green gas
bromine: red-brown liquid
iodine: grey-black solid
6
Q
transition elements
A
physical:
- high density
- high m.p
chemical:
- form coloured compounds
- act as catalysts
- ions with variable oxidation numbers (iron (II) and iron (III))
7
Q
noble gases
A
unreactive + monoatomic gases due to full outer shell
