Unit 1 Chapter 2
Part 1
Chemistry – central science
2. Matter
a. Anything with mass and takes up
space
b. 4 states of matter – depend on
amount of thermal energy
1) Solid
2) Liquid
3) Gas
4) Plasma
1.
c. Elements and atoms
1) Element – pure substance that
can’t be broken down farther by
ordinary chemical reactions
2) Atom – smallest unit of an
element that has the same
characteristics as that element
a) Nucleus
i. Center of atom
ii. Made of neutrons and
protons
b) Neutrons – no charge
c) Protons
i. Positive charge
ii. Tell what element you have
d) Electrons
i. Negative charge
ii. Orbit the nucleus in set
energy level
iii. Determines properties
e) Mostly open space
- If nucleus is the size of a tennis ball
at 50 yrd line the electrons are
pinheads by goal posts
f) Held together by opposite forces
g) Proton – electron relationship
i. Protons = electrons in a
neutral atom
ii. Stars and nuclear reaction
changes number of protons
iii. Possible to lose or gain
electrons
3) Periodic table
a) Lists the elements
b) Organized by atomic number
4) Elements in living things (98%)
a) Oxygen
b) Carbon
c) Hydrogen
d) Nitrogen
e) Calcium
d. Chemical bonding: Ionic
1) Atoms bond for stability
2) 8 electrons in outer shell gives
stability (H only 2)
3) Ions – gain/lose electrons
4) Ionic bonding – bonding of ions
5) Weaker bonds
6) Salt
e. Chemical Bonding: Covalent
1) Sharing electrons
2) Very strong bonds
3) Single, double, triple bonds
4) Water, sugar, methane
f. Compounds
1) Made of 2 or more elements
2) Molecule – smallest unit of a
compound
3) Properties are different than
individual elements
4) Water and sugar
5) Molecular formulas
a) H2O
b) C6H12O6
c) (SO4)3
d) 7CO2
g. Chemical and Physical Changes
1) Chemical
a) Atoms change - electrons
b) Compound’s characteristics
differ from its element’s – NaCl
c) Bubbles, gives of light/heat,
change in color, forms a
precipitate
2) Physical Change
a) Change of state
b) Mixtures
c) Can be separated
1. Ability to do work or cause a
change
2. 2 kinds
a. Kinetic energy (KE) – motion
b. Potential energy (PE) – stored
3. Can be converted to the other
4. Thermodynamics
a. Laws
1) Energy is can’t be created or
destroyed
2) When energy is used some is
lost
b. When energy is used it increases
entropy – burning a log
5. Kinetic molecular energy
a. All atoms are moving
b. More heat = more energy =
more moving
c. Movement determines what state
it will be in
d. Absolute zero – no movement
6. Potential energy of molecules
a. Stored in the bonds
b. Exothermic – gives off heat
c. Endothermic – absorbs heat
7. Catalyst
a. Effects rate of reaction but isn’t
used
b. Heat
1.
2.
3.
4.
5.
Homogeneous mixture (blood)
Solute – thing being dissolved
Solvent – thing doing the dissolving
Concentration – ratio of solute in
the solvent
Dilute
6. Diffusion
a. Movement of molecules from high
concentration to low concentration
b. Stops once equilibrium is reached
c. Concentration gradient – difference
b/w the two areas
d. Permeable – allows things to pass
through
7. Osmosis
a. Semipermeable
b. Diffusion of
water molecules
c. High to low
concentration of
water

https://www.youtube.com/watch?v=QBAPBGa5SBA
Water is polar
a. Molecule has a slight + and – side
b. Oxygen pulls on electrons making it
_
– and H +
c. Creates H-bonds
O
H
H
1) Weak bonds
+
+
2) Form between + H atom and a
slightly - atom
1.
3) Causes adhesion, cohesion, and
high specific heat
a) Adhesion
b) Cohesion
c) High specific heat
i. Allows for homeostasis
ii. Allows for temperature
regulation
2. Polar and nonpolar substances don’t
mix
Acids
a. Release H+ when dissolved
b. H+ = proton
c. Increase concentration of H+
d. 0 – 6.99 on pH scale
1.
stomach acid pH between 1 and 3
more acidic
2. Bases
a. Decrease concentration of H+
b. 7.01 – 14 on pH scale
3. Neutral
a. 7 on pH scale
b. Pure water
bile pH between 8 and 9
more basic
 Google
“osmosis lab”
◦ Click on first link
 http://www.phschool.com/science/biology_place/labbench/lab1
/intro.html