Caesar's Last Breath

1. Caesar's Last Breath • The folklore has it that each time you take a breath it contains some of the atoms/molecules from the last breath exhaled from Julius Caesar, Michelangelo, Ghengis Khan, or for that matter just about any person who died a long time ago. The example quoted is most usually Julius Caesar, and the tale is often known as the "Caesar's Last Breath" phenomenon.

2. Caesar's Last Breath • Strange as it may seem, this is true! Admittedly, some assumptions are made in the reasoning, but it is true. Incidentally, it is not something specific to Julius Caesar or to any other person who has lived, but it is simply a statement that we all breathe the same air, in the same sort of way that a dozen people stuck in a lift all breathe the same air. • Although it seems extraordinary, this business about the "same atoms" is just because the actual molecules of air are extremely small. If they were just "very" small it would not be true, but they are even smaller than that, resulting in singular molecules being mixed.

3. Caesar's Last Breath • The actual calculations: Assuming Julius Caesar's last breath was one liter of air, it would have consisted of about 1022 (exp) (1000000000000000000000) molecules. As he died a long time ago and the air has been all mixed up since then, and atoms don't go away, those molecules are assumed to have been evenly spread throughout the entire Earth's atmosphere.

4. Caesar's Last Breath • Therefore, when you divide it out, it turns out that in the average breath you take, there is a good chance of it containing a molecule or two, which was once part of the last breath of Julius Caesar. • Homework – Re-Read Section 2.2 for Thursday • Ms. Atwood has to cover class. We will finish the rest of the section Friday after the Vocab Quiz. • Looking to do a lab possibly Saturday.

5. Quick quiz on the words • Write down the word and then give the definition. Do not look on someone’s paper and do not talk. • Prokaryotic (Prokaryote) • Cancer • Ecology • Reproductive Isolation

6. Review section 2.1 • The atom – small fragment of a substance, whether chalk, sand, or rocks • Protons and neutrons – found in the nucleus (Protons + Charge) neutrons (no charge or neutral) • Electrons – outer shell which has – charge • Each shell wants to have a maximum number of electrons on its outer shell • 2, then 8, then 14,…

7. Review section 2.1 • Electrons – outer shell which has – charge • Each shell wants to have a maximum number of electrons on its outer shell • 2, then 8, then 14,…

8. Review section 2.1 • Element – pure substance that consists of just one substance (carbon for example) • Isotopes – Differing number of neutrons of the same element are call isotopes. For example Plutonium (Pu 94 –the isotope Pu 239 is radioactive and used for nuclear energy / weapons)

9. Review section 2.1 • Compounds – formed by 2 or more substances • Salt – NaCl

10. Review section 2.1 • Ionic bonding – electrons are transferred

11. Review section 2.1 • Covalent bonding – electrons are shared

12. Review section 2.1 • Van der Waals forces – some atoms have stronger attractions for electrons than other atoms • Simple example - For example – Iron (in your blood) and Oxygen. When Iron deficient you have tired blood and you yourself are tired, but if Carbon-monoxide (CO) enters the body the Oxygen is more attracted to that than the Iron in the blood