Chapter 2: The Chemistry of Life
Name ______________________________
Biology 5.0
Date ________________ Period: ________
Section 2.1: The Nature of Matter
Chemistry: What do I already know?
Three Subatomic Particles
Atomic Symbol
Proton:
Neutron:
Electron:
Atomic Number:

Mass Number:
Valence Electrons
Atomic Mass:
Covalent Bond - ___________________________________________________________________________
Ions - ____________________________________________________________________________________
Cation – ____________________________________________________________________________
Anion – ____________________________________________________________________________
Ionic Bond – ______________________________________________________________________________
1
Molecule – _______________________________________________________________
_________________________________________________________________________
Counting Atoms
Na2SO4
Ca(OH)2
3 Fe2(SO3)3
Isomers – ______________________________________________________
________________________________________________________________
Section 2.2: Properties of Water
What do I already know?
Water
The Water Molecule:
Water has a number of unique properties:
2
Water is a polar molecule:
What is a polar molecule?
What does it look like?

An

The molecule becomes __________________ on each
distribution of ________________
_____________

It means that the electrons are _____________________
______________________________________________
Hydrogen Bonding:
Because of their partial positive and negative charges, polar molecules such as water can attract each other.
Hydrogen Bonding
 Because of their partial
charges,
such as water can
What does it look like?
and
molecules
each other.
 The attraction between a
one water molecule and the
another is known as a
on
on
.
Cohesive and Adhesive Properties:
Cohesion
Example: Surface Tension
Adhesion
Example: Capillary Action
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High Heat Capacity:
What is Heat Capacity?
Why is it so high for water?
Water is the Universal Solvent. Why is it considered the Universal Solvent? ________________________
__________________________________________________________________________________________
Hydrophobic
Examples:
Hydrophilic
Examples:
Why is WATER considered the Universal Solvent? _______________________________________________
__________________________________________________________________________________________
MIXTURES: Homogeneous and Heterogeneous
What is a mixture?
Examples:
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Examples of Mixtures:
Homogeneous Mixture
Examples:
Heterogeneous Mixtures
Examples:
Parts of Solution: All solutions contain…
Solvent
Solute
Application
One
Two
Acids, Bases, and pH:
The water molecule dissociates:
Acids
Bases
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pH Scale
The pH scale ____________________________________________________
_______________________________________________________________
0_____________________________7_____________________________14
Interpreting the pH scale:
Classifying Acids and Bases
Acid
Base
What are BUFFERS?

Weak acids or bases that can _______________________________________________________________
_______________________________________________________________________________________

Produced

The pH value in most cells is ________
o The pH of stomach acid is ________
o The pH of the blood is ________
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Chemical Reactions and Enzymes (Section 2.4):
Energy
Forms of Energy:






Potential
Energy
Kinetic
Energy
Free
Energy
Activation
Energy
What is a chemical reaction?
Reactants:
Products:
Bonds are
In the chemical reaction below, write R over the reactants and P over the products. What does  mean?
CO2
+ H2O 
C6H12O6
+ O2
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Types of Reactions:
Exergonic
Endergonic
Energy Changes in a Chemical Reaction:
The graphs below show the amount of energy present during two chemical reactions. One of the reactions is
an energy-absorbing reaction, the other is an energy-releasing reaction. Label the type of reaction for
each, label the energy level for the reactants and products, then draw an arrow on each to show the energy
of activation.
Type of Reaction: ______________________
Type of Reaction: ______________________
Enzymes
Enzyme
Catalyst
Substrate
Active Site
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How an Enzyme Works
1. Enzymes act on a
. (Shapes fit together like a lock and a key)
2. A small area on the enzyme, called the
specific
, can attract and hold only a
.
3. The enzyme acts as a
, which accelerates the
of the chemical reaction.
4. The enzyme
needed by weakening the chemical bonds in
the substrate.
5. The enzyme is then
.
Regulation of Enzyme Activity

Enzymes work best at certain
and
o Most enzymes in humans work best at

.
C
Denaturation –
o Enzyme becomes
o
and
can cause denaturation
o Some enzymes can be
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