The Modern Periodic Table.
COLUMNS 1,2,3,4,5,6,7 AND 8 ARE CALLED GROUPS.
4 GROUPS ARE GIVEN SPECIAL NAMES.
ROWS OF ELEMENTS ARE CALLED PERIODS.
THE FIRST THREE PERIODS ARE SHOWN BELOW.
PERIOD 1 HAS JUST 2 ELEMENTS.
PERIODS 2 AND 3 ARE SHOWN WITH 8 ELEMENTS.
| Period\Group | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| 1 | H | He | ||||||
| 2 | Li | Be | B | C | N | O | F | Ne |
| 3 | Na | Mg | Al | Si | P | S | Cl | Ar |
PATTERNS OBSERVED IN THE PERIODIC TABLE.
- Metals are found on the left and non-metals on the right.
- Groups 1 and 2 contain only metals.
- Groups 7 and 8 contain only non-metals.
- Mostly, the elements under the “staircase” are metals, and elements above are non-metals.
- Between the metals and non-metals we find metalloids (also known as semi-metals).
These are elements with a combination of metallic and non-metallic properties. - Period 3 shows a change from metals → to semi-metals → to non-metals.
- Group 4 shows a similar change going down: from metals → to semi-metals → to non-metals.
- Most of the elements are metals. [NOTE: when metal elements react to form compounds they no longer have the appearance of a metal.]