1. The Chemistry of Life
Chapter 2

2. I. Nature of Matter A. Atoms- basic unit of an element
Made of 3 subatomic particles:
1. Protons- positive charge, in the nucleus
2. Neutrons- no charge, in the nucleus
3. Electrons- negative charge, circling the nucleus

3. B. Elements and Isotopes
1. Element-one kind of an atom
Periodic table-chart showing all the known and unknown elements
3. Mass number = # protons + # of neutrons
4. Atomic Number = # protons
*in a neutral atom the # of protons, neutrons, and electrons is the same no CHARGE

4. 5. Isotope- atoms of same element, but have different # of neutrons
Examples: Carbon 12, Carbon 13, Carbon 14
Radioactive isotopes-have unstable nuclei that break down ate steady rate over time
Uses? See page 35

5. C. Chemical Compound- 2 or more atoms in a set proportion
1. Represented by a chemical formula
Examples: H2O, CO2, NaCl, O2
*Note: the properties of a compound are very different from the elements they are formed from
2. C6H12O6 means there are 6 Carbon, 12 Hydrogen, and 6 Oxygen atoms

6. D. Chemical Bond- involves the exchange or sharing of valence electrons between atoms
2 main types of bonds
1. Ionic bond- an atom looses or gains an electron, resulting in a positive or negative charge (see pg. 37)
2. Covalent Bond- electrons are shared between 2 atoms

7. There are 2 types of covalent bonds
a. Single bond shares 2 electrons
b. Double bonds share 4 electrons
3. van der Waals forces- slight attraction between opposite charged regions of a molecule *not as strong as an ionic or covalent bond

8. Properties of Water
What do you know about water?

9. A.The Water Molecule Composed of 2 hydrogen atoms and 1 oxygen atom
Polar- an unequal distribution of electrons 1&ei=R4VBUsuVN4WY2gW954BI&q=water+molecules+and+polarity&oq=water+molecules+and+polarity&gs_l=img j c.1.27.img DaVljVYBXGA#biv=i%7C13%3Bd%7CrYNbNY0XOG1CzM%3A
Hydrogen bond- weak bonds between valence electrons so the bonds can easily be broken
*unique qualities of water: expands when it freezes, makes a good solvent, is adhesive & cohesive

10. b. cohesion- attraction of molecules of the same substance. example?
c. adhesion- attraction of molecules of different substances
d. heat capacity- the amount of energy it takes to raise the temperature *water has a high heat capacity. Why is is a good thing?

11. Which is which?

12. B. Solutions and Suspensions
1. mixture-material of 2 or more substances that are mixed but not chemically combined
a. solution= solute + solvent, where components are evenly distributed, example?
What is the best solvent? Why?
b. suspension- water molecules and undis- solved materials, example?

13. C. Acids, Bases, and pH H2O can separate and become H+ and OH- ions
pH scale- scale from 0 to 14 and measures the concentration ( []) of H+ ions
1. 0 most acidic, 7 is neutral, 14 is most basic
2. Acids have high [] of H+ ions and pH below 7; examples?

14. 3. Bases have low [] of H+ ions and pH above 7; examples?
4. Buffers- weak acids or bases that react with strong acids or bases; prevent sudden changes in pH levels

15. Carbon Compounds
A. The Chemistry of Carbon has 4 valence electrons to bond with
1. Carbon bonds with Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, & Sulfur
2. Carbon bonds with other carbons, making it possible to make large chains- macromolecules

16. B. Macromolecules- large molecules
a. monomers- simple molecules
b. polymers- chains of monomers
C. polymerization-formation of macromolecules & polymers
4 groups of macromolecules: carbohydrates, lipids, nucleic acids, and proteins

17. Carbohydrates 1C: 2H:1O a. Main source of E (energy) for living
1. Simple sugars= monosaccharides
example: glucose, fructose, galactose
2. Complex sugars= polysaccharides
example: starch, cellulose, glycogen

18. Lipids: Carbon & Hydrogen
Also known as???
a. Main function- E storage & Structure
1. Saturated-full of H atoms, "bad" fats
2. Unsaturated- not full of H bonds, "good" fats
HDL vs. LDL

19. 3. Nucleic Acids made of: H, O, N, C, P
a. Main function- store and transmit genetic information
b. nucleotides-monomers that make up nucleic acids consist of a 5 Carbon sugar, Phosphate group and a Nitrogenous base

20. DNA vs. RNA DNA= deoxyribonucleic acid
Made w/ sugar called deoxyribose
RNA= ribonucleic acid
Made with ribose sugar

21. *proteins are chains of amino acids
Proteins: C, N, H, O
Main functions-control rates of reactions,regulate cell processes, transports materials, forms muscles & bones
Amino acids-make up proteins (pg. 49), have a n amino group and carboxyl group
*proteins are chains of amino acids

22. Chemical Reactions & Enzymes
A. chemical reaction- process that changes one set of chemicals to another
1. reactants-chemicals that enter the reaction
2. products-chemicals that result from a reaction

23. B. Energy (E) in reactions
1. different types of reactions either release or absorb energy
a.types of reactions that release E:
b. sources of E for reactions:
2. activation E- the amount of E it takes to start a reaction (pg. 51)

24. C. Enzymes
-function in controlling chemical reactions, making things for cells, releasing E, & transferring information
-are biological catalysts that speed up chemical reactions by lowering activation E
1. catalyst-speed up reactions

25. Enzyme-Substrate Complex
a. substrate- the reactant or what is broken down, ends in - "ose"
b. active site- on the enzyme, ends in "ase"
c. products- the resulting product

26. 2. Regulation of Enzymes
a.Things that affect enzyme activity: temperature, digestion of food, other chemical reactions in the body, pH levels