1. Chemistry of Life Exploring Life Chapter 4 By M. Donohue

2. Chemistry in Biology??? -Biology is…and all living things are made up of….MATTER! The study of matter and the changes it under goesAre living things changing? Chemistry Anything that takes up space (V) and has mass (g) Composed of one or more elements Matter Pure substance that cannot be broken down into other substances by chemical means“basic ingredients” of matter; examples gold, helium, oxygen, nitrogen Element Substance containing two OR MORE elements chemically combined in a fixed ratioexample: water, sodium chloride (aka table salt) Compound Smallest possible particle of an element; building block of matter -derived from Greek word “atomos” which means “indivisible” Atom An alternate form of an element; same # of protons, different number of electrons Isotope

3. Elements Pure substances About 25 essential elements to life Trace elements Make up less than 0.01% of body mass but are critical -Over 100…92 naturally occurring and the rest are synthetic/man-made -made up of 1 type of atom Iodine Iron

6. Physical Change/properties Color, shape, texture, amount The actual make-up of matter/substance does NOT change Examples Ripping a piece of paper Painting a wall When two substances are combined to create a new substance with new properties different from those that made it up…Combo of different elements Examples Water H2O Sodium chloride NaCl Chemical change/properties Compounds When 2 or more elements are chemically combined in fixed ratios making a new substance with new properties

7. Atomic Theory Dalton’s Atomic Theory 1) All matter is made of atoms that are indivisible and indestructible. 2) All atoms of a given element are identical in mass and properties 3) Compounds are formed by a combination of two or more different kinds of atoms. 4) A chemical reaction is a rearrangement of atoms.

8. Structure of an Atom -smallest unit of matter that retains properties of element -Atom has an electric charge of zero (all positives equal negatives)

10. You can find this on the periodic table

11. (smaller # by the element…goes in numerical order)

13. (bigger # on PT)

15. Columns (that go up and down) are called GROUPS or FAMILIES

16. Number your columns…1(H),2, skip all the ones that drop down, 3 (B), 4, 5, 6, 7, 8

17. Families share similar characteristicsGroups of friends have similar interests, act the same Elements in the same group/family have the SAME CHEMICAL PROPERTIES They react the same!!

19. Electrons are arranged in “orbitals” around the nucleus

20. First orbital/ring has a maximum capacity for 2 electrons

21. Each ring after has a MAX Capacity for 8 electrons

22. VALENCE electrons are the ones in the outer most ring!

23. Columns of the periodic table tell you how many valence electrons there areThe ELECTRON Cloud

25. # of Electrons

26. # of neutrons

27. Mass #

28. Chemical Reactivity

31. H and He only need 2 to be happy

32. 8 valence e- = 

33. 2 v.e. =  for H and He