1. TRANSITION METALS LOSE DIFFERENT NUMBERS OF ELECTRONS EVEN THOUGH THEY ALL HAVE 2 VALENCE ELECTRONS. Transition Metals

2. Iron chloride There are two different compounds that contain iron and chlorine: FeCl 2 FeCl 3 These two compounds are not the same, so we can not give them the same name.

3. FeCl 2 We know that chlorine wants to gain one electron. Therefore the iron must lose two electrons, since there are two chlorines. This gives the iron a +2 charge because it loses 2 negative electrons. This is written Fe +2 or Fe ++

4. FeCl 3 We know that chlorine wants to gain one electron. Therefore the iron must lose three electrons, since there are three chlorines. This gives the iron a +3 charge because it loses 3 negative electrons. This is written Fe +3 or Fe +++

5. Names? FeCl 2 is called Iron(II) chloride because each iron atom is losing two electrons. FeCl 3 is called Iron(III) chloride because each iron atom is losing three electrons. The Roman numerals in the parenthesis is the number of electrons lost by one atom of the transition metal.

6. What is the formula? What is the formula for Copper(I) bromide? What is the formula for Iron(III) oxide? Try these, then go to the next frame for the answer

7. Answers! What is the formula for Copper(I) bromide? Bromine always gains one electron and the copper wants to lose one electron. Therefore the formula is CuBr.

8. Rust What is the formula for Iron(III) oxide? Oxygen wants to gain two electrons. Iron wants to lose three electrons in this case. (III) You will need two iron atoms to lose 6 electrons and three oxygen atoms to gain 6 electrons. The formula is Fe 2 O 3.