1. Characteristics of Life: Properties of Water (Part 3)

2. Properties of Water essential abundant Cells POLAR sharing electrons
III. Water – “Where there’s life…….there’s water!!” Water is the most ___________ and ____________ substance on Earth. ______are made up of mostly water and most cells are surrounded by water. The importance of water is largely due to its unique characteristics, which all directly relate to one very important property of water… Water is _________!!!!
essential
abundant
Cells
POLAR
A. Polarity
1. Definition of Polarity
a. The UNEQUAL __________of ___________ in molecules formed with covalent bonds.
sharing
electrons

3. Properties of Water polar hydrophilic water loving nonpolar repel
2. Hydrophilic vs Hydrophobic
a. Polar molecules are attracted to other ________ molecules, and is therefore described as _______________.
“Hydro” = _______, “Philic” = ________
Ex: salts, sugars
b. Non-polar molecules are attracted to other ___________ molecules and will _______ polar molecules such as water.
These molecules are referred to as being ________________
“Hydro” = ________ , “Phobic” = __________
Ex: fats, oils
polar
hydrophilic
water
loving
nonpolar .
repel
hydrophobic
water
fearing

4. Properties of Water
B. Water Properties – Polarity gives water some unique properties important in maintaining _______________.
homeostasis
sticky
1. Water is “________” - Water molecules tend to stick together, called __________ and results in ________ _________which is the measure of how difficult it is to stretch or break the surface of a liquid.
Water molecules also tend to stick to other __________ – known as ___________. This explains the phenomenon known as __________ action.
cohesion
surface tension
surfaces
adhesion
capillary

5. Properties of Water
Water is the solvent of life – water dissolves many substances due to its _______. Slightly-charged ends of water molecules _______ and _________ atoms that make up other compounds, thus dissolving them.
Anything dissolved in water is referred to_______. The resulting substance is known as a ________.
Other _______ substances dissolve very easily in water. This is important
to living systems because many important compounds in cells are in solution.
Polarity
attract
separate
solute
solution
polar

6. Properties of Water
C. _________ – tool used to measure the strength of an acid or a base, on a scale from 0-14
1. Acid – taste ____, turn litmus paper _____ (example: _______, lemon juice)
2. Base – taste ______, turn litmus paper _____, (example: cleaning products like Drain-o, _______, _____ ____.)
pH Scale
sour
red
vinegar
bitter
blue
bleach
Dish soap