1. The Chemistry of Life

2. Atoms The basic unit of matter Greek, atomos meaning “unable to cut”
Named after Democritus...there has to be a limit =atom.

3. Atoms What does an atom consist of?
Subatomic particles: protons (+), neutrons, and electrons (-).
What is the center of an atom called?
Nucleus
Where do we find electrons?
Constant motion surrounding the nucleus.

4. SUBATOMIC PARTICLES
Why are atoms neutral despite having charged particles?
Atoms have equal numbers of electrons and protons/have equal, but opposite charges.
(they balance out)

5. Elements and Isotopes What is a chemical element? What is an isotope?
A chemical element is a pure substance that consists entirely of one type of atom (C, Na, H, N, O, etc.)
What is an isotope?
Atoms of the same element w/ different number of neutrons.

6. Isotopes of Carbon
Nonradioactive carbon-12
Nonradioactive carbon-13
Radioactive carbon-14
6 electrons
6 protons
6 neutrons
8 neutrons
7 neutrons
Because they have the same number of electrons, all isotopes of an element have the same chemical properties.

7. Chemical Compounds What is a chemical compound?
Substance formed by the chemical combination of two or more elements.
H20, NaCl, C6H1206

8. Chemical Bonds What are the main types of chemical bonds?
Ionic & Covalent
Ionic- electrons transfer from one atom to the other.
Sodium atom (Na)
Chlorine atom (Cl)
Sodium ion (Na+)
Chloride ion (Cl-)
Transfer
of electron
Protons +11
Electrons -11
Charge
Protons +17
Electrons -17
Electrons -10
Charge
Electrons -18
Charge

9. Chemical bonds
Covalent Bonds- electrons are shared b/w atoms = molecule.
What molecule is this?

10. Hydrogen Bonds
Cohesion: attraction b/w molecules of the same substance.
Surface tension is caused by the attraction of molecules to each other
Adhesion: attraction b/w different substances.
Meniscus

11. Properties of Water
Water is polar: there is an uneven distribution of electrons b/w the oxygen and hydrogen atoms.
Why is this important?
Water can react to form
ions:
H20 -> H+ + OH-
Hydrogen ion Hydroxide ion

12. Acids, Bases, and pH pH: ranges 0 to 14
Acids: contain higher [ ] of H+ ions than pure water and have a pH below 7.
Bases: contain lower [ ] of H+ ions than pure water and have pH values above 7.

13. Buffers
Weak acids or bases that can react w/ strong acids or bases to prevent changes in pH.
Why is this important?

14. Carbon Compounds
What is the difference b/w organic/inorganic chemistry?
Carbon
Carbon forms strong covalent bonds and can join other carbon atoms to from long chains (carbon-carbon bonds)
Four valence electrons
No others like it.

15. Macromolecules Four groups of organic compounds “Giant molecules”
Carbohydrates (starch and sugar)
Living things main source of energy
Monosaccharide's/polysaccharides, “ose”
Lipids (cooking oil)
Mostly CH, used to store energy
Saturated, unsaturated
Nucleic Acids (RNA & DNA) (CHNOP)
Proteins (polymers of amino acids) (CHNO)
AA are compounds w/an amino group (-NH2) and a carboxyl group (-COOH), what distinguishes each AA?

16. Amino Acids
General Structure

17. Recognizing Macromolecules
Organic or Inorganic?
Nucleic Acid
Glucose
Lipids

18. Chemical Reactions & Enzymes
Why are chemical reactions important?
Chemical reaction: a process that changes into another set of chemicals.
CO2 + H2O H2CO3
H2CO CO2 + H2O
What are reactants? What are products?
Chemical reactions always involve the breaking of bonds in reactants and the formation of new bonds in products.

19. Energy in Reactions
To stay alive organisms need to carry out reactions.
Growing, breathing, think, etc.
Activation energy: the energy needed to get a RxN started.
Can you tell which is an energy absorbing reaction/energy releasing reaction?

20. Enzymes Some chemical reactions are too slow...
Catalyst: substance that speeds up the rate of a chemical reaction; lowers activation energy
Enzymes (“ase”) are biological catalyst; speed up chemical reactions that take place in the cell.
Lipase
Carbonic anhydrase
Amylase

21. Enzyme Action How do they work? Enzyme-Substrate Complex
The reactants of enzyme-catalyzed reactions are known as substrates.
Not random; active site and substrate fit like “lock and key”
What happens after?
What factors affect enzyme function?