Download Chemistry Review - Petal School District

Review

Atom—the building block of
matter; the smallest unit
of an element; Made up
of 3 subatomic particles:
Nucleus—which contains:
1. protons—positive charge
2. neutrons—no charge (neutral)
Energy levels—which contain:
3. electrons—negative charge
 Element—pure
substance made
up of only ONE kind of atom;
found on periodic table
 Compound—atoms of two or
more different elements
combined chemically
*Elements in a compound do
NOT retain their properties.
Chemical bonds—hold atoms
together chemically
 Types of Chemical Bonds:
1. Ionic bond—formed by
TRANSFER of electrons
Example of Ionic compound:
NaCl (table salt)

2. Covalent bond—formed by
SHARING of electrons; these are
found in most life substances
Examples of covalent compounds:
Organic compounds—such as
C6H12O6 (glucose)
Water
3. Hydrogen bond—ex: connect water
molecules to one another
4. Peptide bond—hold amino acids
together in a protein
 Chemical
Reactions—are
represented by a chemical
equation
Ex: 2Na + Cl2→ 2NaCl
Reactants → Products
Acid—A compound that produces
hydrogen ions (H+) or hydronium
ions (H3O+) in solution
pH of an acid = less than 7
The more hydrogen ions an acid
has, the stronger the acid is.
Base—A compound that produces
hydroxide ions (OH-)
pH of a base = greater than 7
The more hydroxide ions a
base has, the stronger the base is.
Neutral—Not an acid or a base
neutral = 7
The farther an acid or base’s pH is
from 7, the stronger the acid or base.
pH Scale:
0
acids
7
neutral
14
bases
Buffers—substances that have
the ability to neutralize acids
Ex: blood
 Water
is the universal solvent.
 Most chemical reactions in
organisms require water.
 Most organisms consist of
70-95% water.
 Water
is a polar molecule
—has + pole and - pole!
 Water resists temperature
change.
 Water expands as it
freezes.
 Adhesion—water’s
attraction for certain other
substances
 Capillary action is related
to adhesion.
 Cohesion—water’s
strong
attraction for water
 Surface tension, high heat
of vaporization (high
specific heat) are results of
cohesion.
1. What are atoms with an
electric charge called?
A. molecules
B. electrons
C. polar
D. ions
2. Molecules that have an
uneven pattern of electric
charge (more positive in one
area; more negative in
another) are said to be
________.
A. nucleic
B. polar
C. non-polar
D. ionic
 Organic
means made of
carbon(C), hydrogen(H),
and oxygen(O).
 Inorganic means NOT
made of C, H, and O!
Water is inorganic!!!
1.
2.
3.
4.
Carbohydrates
Lipids
Nucleic Acids
Proteins
 Building
blocks →
monosaccharides
 Function → to store and
release energy


Building blocks→
glycerol and fatty acids
Functions→
*Main component of the cell
membrane (phospholipids)
*Long-term energy storage
*Padding, insulation, waterproofing, flotation
Building
blocks→
nucleotides, each
made of: sugar
phosphate
nitrogen base
 Function
→
DNA-contains
genetic
information
RNA-used in protein
synthesis
ATP-provides energy!
Nitrogenous base
(A,G,C, or T)
Phosphate
group
Phosphate
Thymine (T)
Sugar
(deoxyribose)
Base
Sugar


Building blocks→amino
acids
Functions →
*Build structure in organisms
*Speed up (CATALYZE) chemical
reactions as enzymes
*Is a component of the cell
membrane

Substrate—the reactant (substance)
on which the enzyme works
The
enzyme can only work
on a
specific
substrate!
Enzymes
remain
completely unchanged
by the reaction.
Enzymes work through
the Lock and Key
method.
3. NO other kind of atom can form
the number and variety of
molecules that ___________________
can because it can bond to 4 other
atoms at the same time to make
carbohydrates, lipids, nucleic acids,
and proteins.
A. hydrogen
B. oxygen
C. carbon
D. sodium
4. A ____________________ is
made up of a sugar, a
nitrogen base, and a
phosphate group.
A. amino acid
B. nucleotide
C. phospholipid
D. glycoprotein
5. Glycogen, cellulose, and
starch are all
__________________.
A. proteins
B. polysaccharides
C. nucleic acids
D. lipids
E. phospholipids
6. Reactants in an enzymecatalyzed chemical reaction
are called __________________
A. polymers
B. products
C. substrates
D. organics