1. LIVING THINGS Properties of Water And Acids/Bases HEADINGS VOCAB
IMPORTANT INFO

2. Living Things Use & Need Energy
a.) Energy comes from food, used to maintain body
b.) AUTOTROPH: produce own food
c.) HETEROTROPH: must consume food
d.) DECOMPOSER: breaks down dead material for food

3. Living Things Respond to their Surrounding
a.) Reaction to a stimulus
b.) Action causes a reaction
c.) Reaction is called a response
d.) Involves one individual

4. Question: Describe the properties of water that make it important to living things.
Water is polar
it has an uneven distribution of electrons between the hydrogen and oxygen atoms
One side is positive, the other is negative

5. Water Properties: A. Water is Cohesive: attraction B/T same molecules
causes molecules to draw inward at surface
Ex: Some insects & spiders can “walk” on the surface of H2O
B. Water is Adhesive
Adhesion in water is when the water is 'sticky' or attracted to other surface
Attraction between different mol.
Causes H20 to bend at surface
Ex: Capillary action-pulls column of water up to the top of a plant
Water Properties:

6. Water is called the “Universal Solvent”: dissolves many other substances due to polarity
Differences in charges pulls/pushes substances apart
Water exhibits evaporative cooling: removes heat when it evaporates from a surface
Ex: sweating cools skin
Water expands during freezing: expands into crystal formation releasing heat
Ex: rocks broken up by ice creating soil; ice layer protects fruit from freezing

7. Acids, Bases and the pH scale
a.The pH scale measures the concentration of H+ ions
How acidic something is)
b. Ranges from 0-14
c. At 7: H+ ions and OH- ions are equal so it is neutral
d. ACIDS: release H+ when mixed with water
0-7: acidic, has more H+ ions

8. 7-14: basic, has more OH- ions
Sour, corrosive
Ex: HCl, H2SO4
Always have H+ at front of formula
e. BASES: release OH- when mixed with water
7-14: basic, has more OH- ions
Bitter, slippery, usually in cleaners
Ex. NaOH, CaOH
Always have OH- at end of formula *

10. What is a buffer?
Buffers are weak acids/bases that react with strong acids/bases
prevent sharp changes in pH
Helps to neutralize
Helps control pH in blood, digestive tract, etc. = maintain homeostasis (internal balance)

11. Quiz : The following are all examples of the characteristics of life
Quiz : The following are all examples of the characteristics of life. Identify each one.
Adapt D. genetic code G. Respond to stimulus
Made of cells E. Grow and develop H. Homeostasis
Reproduce F. Use/need energy
You eat a hamburger for lunch.
A baby gains 3 pounds in one week and begins to recognize voices.
A polar bear has white fur to blend in with the snow.
Your start to cry whenever you get a shot at the doctor’s office.
You begin to shiver because it is cold outside.
Red and white particles make up part of your blood.
A chick breaks out of an egg.

12. 8. Your saliva measures 7 on the pH scale, it is a(n) ___ solution?
a. acidic b. basic c. neutral
9. The ___ property of water helps in the formation of soil.
a. capillary action b. expansion during freezing c. evaporative cooling
10. Laundry detergent typically has a pH of 3 which indicates a(n) ___ solution?
a. acidic b. basic c. neutral
11. The use of ___ helps to maintain a certain pH in our bodies maintaining homeostasis.
a. buffers b. bases c. acids
12. The ___ property of water removes heat helping to cool your skin through sweating.
a. capillary action b. evaporation c. cohesion