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Fill in the Blank
Is this a mixture or pure substance?
Mixture
______________________
Cl
H
O
H
H
O
O
O
H
Na
O
O
True or False
This mixture contains three compounds.
False, there are only two (water & salt)
________________________________
Salt
Cl
H
O
Na
O
H
H
O
O
O
H
Water
O
True or False
There are ten molecules in this mixture.
True
_____________
Cl
H
H
O
H
Cl
H
O
O
O
Fill in the Blank
Below is a mixture of compounds and elements.
What is the element?
Oxygen
___________________
H
Cl
H
Na
O
Oxygen
H
Cl
Oxygen
Drawing
How many bonds can carbon form?
Four bonds
Draw a model of CH4.
H
H
C
H
H
Multiple choice
Which is the correct configuration
for the compound C2H3OH?
O
H
C
A
C
H
C
H
C
B
O
C
H
H
H
O
C
H
H
C
H
D
H
O
H
H
H
C
H
C
H
H
Drawing
Draw the structure for CH3OH?
H
H
C
H
O
H
Element or Compound?
Indicate whether each the following
substances is an element or compound.
Carbon
Oxygen
Carbon dioxide
Hydrogen
Water
C
O
CO2
H
H2O
Element
Element
Compound
Element
Compound
Element or Compound?
Indicate whether each the following
substances is a mixture or pure substance.
Salt
Water (distilled)
Seawater
Sugar
Salad dressing
Pure substance
Pure substance
Mixture
Pure substance
Mixture
Short Answer
Name the three particles that make
up atoms and indicate their charge.
Proton
Electron
Neutron
+
(positive)
(negative)
(neutral)
Multiple Choice
Where are electrons found in an atom?
A.
B.
C.
D.
Outside the nucleus
Inside a proton
Within the nucleus
Inside a neutron
+
+
Multiple Choice
What is the mass number of the
atom shown below?
A.
B.
C.
D.
2
3
5
7
+
+
Multiple Choice
Which nuclei is not an isotope of the other two?
+
+
A.
+
+
B.
+
C.
Short Answer
What is the atomic number of the
atom shown below?
+
+ +
3
Multiple Choice
Which of the following is a substance formed
by the chemical joining of two or more
elements in definite amounts, like H2O
A.
B.
C.
D.
Isotope
Compound
Nucleus
Enzyme
Multiple Choice
Which of the following represents the
best model of a water molecule?
H O H
A.
O
H
B.
O
O H O
C.
H
O
H
D.
Yes or No
When the elements sulfur and iron are mixed and
heated in a test tube, they react to form iron pyrite
(fool’s gold). Would you expect iron pyrite to retain the
magnetic properties of iron or the smell of sulfur?
Δ
+
Sulfur
Iron
Fool’s gold
No Chemical reactions rearrange atoms into new
substances with different properties.
Short Answer
What kind of chemical bond is shown
below and how do you know?
A covalent bond.
Because the atoms
are sharing the
electrons.
Short Answer
What type of ion is formed when an
atom loses an electron?
A positive ion.
+
+
+ +
Short Answer
What property of water enables water to cling
to the surface of a glass or to a toothpick?
Adhesion, which means molecules of different
substances are attracted to each other.
Multiple Choice
Which shows the correct polarity of a
water molecule?
H
O
H
H
O
H
H
O
( )
H
H
( )
O
H
( )
( )
A.
B.
C.
D.
Short Answer
What kind of mixture is paint or blood?
They are suspensions, which means
they contain particles that will
eventually settle out.
Short Answer
In our blood, the enzyme carbonic anhydrase
carries out the following reactions in order to
prevent sharp, sudden changes in blood pH.
Carbonic anhydrase
What kind of system is this?
A buffer system
Short Answer
What property of water enables insects
and paper clips to float on its surface?
Cohesion, which means molecules of the same
substance are attracted to each other.
Short Answer
What kind of chemical bond is shown
below and how do you know?
An ionic bond.
Because the electron was
completely transferred
from one atom to another
rather than being shared.
This causes each atom to
develop a charge (become
an ion).
Short Answer
What kind of mixture is air or salt water?
They are solutions, because all the
components are evenly distributed.
Short Answer
Which has the higher heat
capacity—water, metal, or air?
Water does. It can absorb a lot of heat
without its temperature rising too much.
Matching
Which pH values would you assign to the
following chemicals:
•
•
•
•
•
Pure water
Stomach juice
Oven cleaner
Lemon juice
Soap
7
1 to 2
13 to 14
2 to 3
9 to 10
Short Answer
Is this liquid acidic, basic, or neutral?
How do you know?
Neutral Because there is an
equal number of H+
ions and OH- ions.
Drawing
Draw a model of carbon dioxide.
O
C
O
How many double bonds does
carbon dioxide have?
Two double-bonds
Drawing
Draw a model of acetylene (C2H2).
H
C
C
H
What kind of bond is this?
A triple bond
Short Answer
A 3-month old sits strapped in a car seat on a hot
July day because her dad forgot she was in the
car. Her body temperature climbs to 105 °F (41
°C). What may happen to the enzymes in her
body if her temperature continues to climb?
Her enzymes will unravel
(denature) and she will die.
Drawing
Draw an amino acid.
H
H
Amino
group
N
H
C
O
C
R
Variable group
H
Carboxyl
group
Label the functional groups.
Short Answer
Is this liquid acidic, basic, or neutral?
How do you know?
Basic
Because there are more OHions than H+ ions in solution.
Short Answer
Complete the following table
Polymer
Monomer
Protein
Amino acid
Polysaccharide
Monosaccharide
Nucleic acid
Nucleotide
Short Answer
What reagent is used to test
for proteins?
Biuret's solution
What color does Biuret’s turn if
proteins are present?
Lavender to purple
Short Answer
What is another name for monosaccharides?
Simple sugars
Short Answer
What reagent is used to test
for simple sugars?
Benedict’s solution
What color does benedict’s turn
if simple sugars are present?
Yellow to orange
Short Answer
Complete the following table
Monosaccharides
Disaccharides
Polysaccharides
Galactose
Sucrose
Glycogen
Glucose
Fructose
Lactose
Cellulose
Maltose
Starch
Short Answer
In what polysaccharide do animals
store their excess sugars?
Glycogen
Short Answer
In what polysaccharide do plants
store their excess sugars?
Starches
Short Answer
What reagent is used to test
for starches?
Lugol’s (iodine) solution
What color does Lugol’s turn if
starches are present?
Purple to Black
Short Answer
What polysaccharide gives plants
their rigidity and support?
Cellulose
Short Answer
Complete the following table
Nucleic acid
Shape
Function
ATP
Single nucleotide
Energy storage / release
RNA
Single Stranded
Protein synthesis template
DNA
Double-helix
Storing hereditary Info
Short Answer
What does the abbreviation DNA stand for?
Deoxyribonucleic acid
Short Answer
What does the abbreviation ATP stand for?
Adenosine triphosphate
Drawing
Draw and label a simple model
of a triglyceride lipid.
3 Fatty-acid tails
Glycerol
Short Answer
Is this liquid acidic, basic, or neutral?
How do you know?
Acidic Because there are more H+
ions than OH- ions in solution.
Short Answer
What happens to the chemical
bonds in a chemical reaction?
Some bonds are broken and
new ones are formed.
Short Answer
What happens to the atoms in
a chemical reaction?
Atoms are never destroyed but only
rearranged into new combinations.
Short Answer
Identify the reactants and products
in the following chemical equation:
methane
oxygen
Carbon
dioxide
water
CH4 + 2O2
CO2 + 2H2O
Reactants
Products
Drawing
Draw an energy releasing graph and
label it using the following terms.
Activation energy
Reactants
Energy
Reactants
Products
Activation
energy
Products
Course of Reaction
Drawing
Show how the following reaction will
change when a catalyst is added.
Without
catalyst
Energy
Reactants
With
catalyst
Course of Reaction
Activation
energy
Products
Short Answer
What is the optimum pH for
each enzyme?
Enzyme
Activity
7.0
X
11.0
Y
4 5 6 7 8 9 10 11 12 13 14
pH
Short Answer
One of the enzymes below functions in
humans and the other is used in an industrial
plant. Which one is the human enzyme?
How do you know?
7.0
11.0
Enzyme
Activity
Enzyme X
X
Y
Most of the cells
in the human
body operate
around pH 7. A
pH of 11 is too
extreme for the
human body.
4 5 6 7 8 9 10 11 12 13 14
pH
Short Answer
According to the graph below, at what pH do
enzymes X and Y have the same amount of
activity? How do you know?
Enzyme
Activity
A pH of 9.
9.0
X
Y
Both activity
curves cross
at pH 9.
4 5 6 7 8 9 10 11 12 13 14
pH
Short Answer
Study the diagram below. What is the
black area on the brown enzyme called?
Active
site
Short Answer
What is the circled substance called?
Active
site
Substrate
Short Answer
What is different about the
enzyme in the yellow circle?
Active
site
Substrate
The substrate
has bound to the
active site
Short Answer
What is the circled complex called?
Active
site
Substrate
The substrate
has bound to the
active site
Enzymesubstrate
complex
Short Answer
What is happening in the
black circled area?
Active
site
Substrate
The substrate
is being
converted
into products
The substrate
has bound to the
active site
Enzymesubstrate
complex
Short Answer
What is shown in the white oval?
Products that
were released
The substrate
is being
converted
into products
Active
site
Substrate
The substrate
has bound to the
active site
Enzymesubstrate
complex
Short Answer
If the substrate is sucrose, then
what is the brown enzyme called?
Products that
were released
The substrate
is being
converted
into products
Active
site
Sucrose
Sucrase
The substrate
has bound to the
active site
Enzymesubstrate
complex
Short Answer
If the substrate is sucrose, then
what are the products called?
Active
site
Sucrose
Glucose
Fructose
The substrate
is being
converted
into products
Sucrase
The substrate
has bound to the
active site
Enzymesubstrate
complex
Short Answer
What suffix do most enzymes end with
-ase
Examples:
Sucrase: Breaks down table sugar (sucrose)
Carbonic anhydrase: Buffers blood
Catalase: Breaks down hydrogen peroxide
Amylase: Breaks down starches
Lipase: Breaks down fats
The End