Aim: How do chemists write “half- reactions”?

•Each atom has a nucleus, with an overall positive charge, surrounded by negatively charged electrons.

•Each electron in an atom has its own distinct amount of energy.

•An oxidation-reduction (redox) reaction involves the transfer of electrons (e-).

Aim: How do chemists analyze reduction-oxidation reactions?

• Reduction is the gain of electrons.• Oxidation is the loss of electrons.• Oxidation numbers (states) can be assigned to

atoms and ions. Changes in oxidation numbers indicate that oxidation and reduction have occurred.

Aim: How do chemists analyze reduction-oxidation reactions?

• In all chemical reactions there is a conservation of mass, energy, and charge.

• In a redox reaction the number of electrons lost is equal to the number of electrons gained.

Aim: How do chemists analyze reduction-oxidation reactions?Essential Questions:

• Why is it only electrons that are transferred in chemical reactions?

• How does one assign oxidation numbers?• How do chemists determine which elements are

oxidized and which elements are reduced in a “redox” reaction?

• Why does reduction and oxidation always occur simultaneously?

• Draw an electron dot diagram depicting a redox reaction.

Aim: How do chemists analyze reduction-oxidation reactions?

• Distinguish between Cu0 and Cu2+ in terms of appearance in their natural state.

• Propose a method to protect iron structures like the Golden Gate Bridge in San Francisco from oxidation.

• Your friend believes the Statue of Liberty is painted green. Use scientific evidence to support your argument that the Statue of Liberty is NOT painted green.

• Predict what would happen if copper ore, which is copper(II)oxide, is heated in the presence of charcoal (carbon.)