1. 4.5 Naming and Classifying elements (Sec 6.2 pg 188)

2. The names of the elements were inspired by a wide range of things. Some are named for properties, others for scientists or cities. Many of the ancient elements originally had Latin names and still have Latin symbols.

3. SYMBOLS: With hundreds of elements scientists needed a symbolic way to represent them all. The symbol system was developed by a Swedish Chemist named Jons Jakob Berzelius.

4. SYMBOLS: His system was ideal because it allowed combinations of symbols to easily be used to show the composition of compounds. – Each element has a 1 or 2 letter symbol. Only the first letter is capitalized so that you can tell when a new symbol starts. – The first letter comes from the start of either the common name or Latin name. – If there needs to be a second letter to avoid confusion it must come from the name and not duplicate another symbol. Some examples: Carbon = C; Chromium = Cr, Copper = Cu

5. SYMBOLS: To show that more than one of the element was in a compound he represented the amount shown with subscripts. – H 2 O = 2 hydrogen and 1 oxygen.

6. METALS, NON-METALS, METALLOIDS: A common way of classifying elements is to put them into groups with other chemicals that have similar properties. There are three large groups: metals, non-metals, and metalloids.

7. Metals: – Many of the elements discovered earliest. (gold, copper, iron, etc) – The largest group of elements. – Properties include: shiny, malleable, ductile, conductive, solid, dense, some react with acid and water. (see Table 2 pg.190)

8. Non-metals: – Properties: dull, brittle, low melting point, gas form, non-conductive. (see Table 3 pg.191)

9. Metalloids: – Properties: properties of both metals and non-metals. – Many are semi-conductors which is useful for electronics.