Transcript Slide 1

CHM130 study guide for final exam.
Instructor: Ken Costello
Visuals
Topics
Building Blocks
Forces & Energy
Mathematics
Obsidian density is 2.4 g/cm3.
The mass of an obsidian arrow
head is 7.2 grams. What is its
volume?
A. 7.2 cm3
B. 3 cm3
B
C. 3 grams
D. 3 times
1. Stone tool
technology
depended on
finding rocks with
glass-like
properties.
Obsidian was one
of them.
What are the two primary
elements that make up
glass?
2. When a clay
pot is fired, a
chemical change
occurs which
makes it
waterproof and
harder.
When clay is fired, what
compound is driven off?
3. Food stored
will spoil unless
something inhibits
the growth of
bacteria and
mold.
Bacteria absorb dissolved
nutrients to survive. What
compound do you eliminate to
stop this process?
How does salt pull water out of
food?
Water
Or water has + & - charges that B. 0.75 mL
pull on the salt.
C. 1333 cc
What kind of bond is there
between these elements?
Covalent
Silicon and oxygen
Water
Firing requires high temperatures. Ceramic instructions says fire at
1000°C. Your kiln temp gauge is
Name three fuels that ancient
in Fahrenheit, what do you set it
people used. (3pts)
to? (F=C*9/5+32)
Animal fat
A. 9032 °F
Wood
B. 243°F
D
Animal Dung
C. 587 °F
(anything flammable)
D. 1832 °F
Salt has + & - charges that
pull on water
Wine is preserved with 120mg
per liter sulfur dioxide (SO2). Your
doctor says you can have 90 mg.
How much can you drink?
A. 750 mL
D. 1.33 L
A
Visuals
Topic
Building Blocks
Forces & Energy
Mathematics
4. Supernovas are
responsible for
creating the 100+
elements we know
of.
Looking at the atomic weights,
what element needs to fuse with
oxygen to make silicon?
Millions of degrees are needed
for elements to fuse together.
Why?
The remains of a supernova are
neutrons at density of 454 billion
g/cm3. A teaspoon (5 cc) of this
weighs how many lbs.?
A. 17 battleships (5 billion lbs)
Carbon.
To overcome electron
to electron & proton
to proton repulsions
B. 9 locomotives (1 million lbs)
C. 454 billion lbs.
D. 1 million grams.
5. The Periodic
Table of the
Elements
organizes
elements in rows
and columns.
6. The Periodic
Table of the
Elements
organizes
elements in rows
and columns.
If sodium had been the building
block, find an alternative with
similar properties.
One of these: Potassium (K),
Lithium (Li), Rubidium (Rb), or
any from Group 1A.
[Letters are good. Name not
needed]
Which column in the Periodic
Table has elements that pull the
hardest on electrons?
1A and 7A
Triphosphorus tetraoxide
Or triphosphorus tetroxide.
Twice
Or 17
Which two columns have
What kind of bond is there
elements that combine with between these elements?
each other the most
aggressively?
Ionic
Name this compound
P3O4 (2pts)
How many times heavier is sulfur
compared with oxygen?
7A
Electronegativity measures
attraction to electrons: F=4.0,
Na=0.93, K=0.82, Cl=3.16.
Which has stronger bond, NaF or
KCl?
NaF
Or 1 and 17
7. These seven nonmetals combine to
make poisonous
gases. Knowing which
gases are lighter or
heavier than air could
save your life.
A
Air inside a hot air balloon is a
mixture of nitrogen, oxygen,
carbon dioxide, water vapor, and
carbon monoxide. What force is
causing the hot air balloon to
rise?
Gravity.
To compare densities of gases,
compare molecular weight.
Which is more dense, nitrogen
monoxide or carbon monoxide?
Nitrogen monoxide.
Visuals
Topic
8. Groups 1A, &
2A are called
alkali metals &
alkali Earth
metals. The
name “alkali” is
Arabic for the
saltwort plant.
Building Blocks
Forces & Energy
The ashes of the Al Kali plant
Lab students are warned about
contain hydroxides (OH-) of groups adding acids (H+) to bases (OH-).
1A & 1B. These neutralize acids
These neutralize each other, so
(H+) to make what?
what’s the problem?
Mathematics
One mole of Ca(OH)2 is mixed with
2 moles of H2SO4. How many
moles of water is produced?
2 moles
A lot of heat is produced.
Water
(optional) It may boil and
splash.
9. Water absorbs Draw a water molecule. Label
heat well, which atoms and show where partial
is why it’s used in charges are..
car radiators.
+
H
H
O
10. One food
When sugar is “burnt” for energy,
calorie is actually it makes the same two building
1000 calories.
blocks that built it, which are…?
So a 1000 calorie
milkshake is
Carbon dioxide and water.
actually 1 million
calories (1,000
kcal).
How many calories is needed to
What causes water to have a
higher than expected boiling point? raise 53 gallons (200 Liters) of
water in a water heater from 20°C
(room temp) to 70°C?
The + & - ends of
water pull on each
other.
A. 10,000 calories
Cellulose is made of chains of
glucose. Why don’t we get
calories (energy) from eating
cellulose?
A (1000 kcal) milkshake can run a
40 watt bulb for how many hours?
(note: 1 calorie produces 4 watts
for 1 sec.)
We don’t have the enzymes
to break up the cellulose into
glucose.
A. 28 hours
B. 100,000 calories
C
C. 10,000,000 calories
B. 0.03 hours
A
C. 40 hours
D. 69 hours
11.Living things
are built from 6
elements with a
few metals
needed for
certain proteins.
What are those 6 elements? 6pts
Hydrogen
Carbon
Oxygen
Nitrogen
Sulfur
Phosphorus
In living things, energy from sugar Energy from ribose comes from
makes ATP which provides energy this reaction. Balance it.
for reactions. How many
phosphate groups are in ATP?
__C5H10O5 + _5O2 
_5CO2 + _5H2O
3
Visuals
Topic
Building Blocks
Forces & Energy
Mathematics
12. Supernova
explosions spread
elements all over the
universe. Gravity
collects elements to
form new stars and solar
systems.
Helium is 2nd most abundant
element in universe, yet very
little is on Earth. Why? (2pts)
What would a helium balloon do
if released on surface of the
moon? Why? (2 pts)
Abundance is given in %, ppm,
or ppb. Write these as fractions.
(3pts)
Being light it is lost to space.
Being inert, it doesn’t bond.
It would fall.
1/100,
Gravity is the reason
1/1,000,000
(optional: there is no air to lift it)
1/1,000,000,000
13. Atoms are too
small to count, so
chemistry resorts to
indirect ways of
counting. I call it
the art of counting
without counting.
Making trillions of molecules of
CO2 is easy: burn coal. Why is
making one molecule hard?
Gas pressure depends on the
speed of the gas molecules.
How does temperature affect the
speed?
Speed is proportional to
temperature
(or temperature goes up, speed
goes up.)
The ideal gas law is PV=nRT.
The symbols stand for what?
5pts
P=pressure
V=volume
n=moles
R=0.0821
T=Temperature
14. In chemical
reactions elements
rearrange
themselves.
A solution of sodium sulfide
[Na2S] and cadmium nitrate
[Cd(NO3)2] are mixed to make
yellow precipitate of cadmium
sulfide [CdS] and aqueous
sodium nitrate. What kind of
reaction is this?
Water pulls on compounds that
have a charge. Sometimes this
dissolves them. When one of the
compounds to the left is not
soluble in water?
If 144.5 grams of cadmium
sulfide precipitate was produced.
How many atoms of cadmium is
in the precipitate?
CdS (or cadmium sulfide)
B. 112.4
They are too small to see or
handle.
Double replacement
15. Crime labs use color
tests (spot tests) to
screen for drugs. One
common one is the
Duquenois-Levine Test
for testing marijuana.
Chemicals needed are
acetaldehyde, ethanol,
vanillin, hydrochloric
acid and chloroform.
What are the formulas for
ethanol, hydrochloric acid, and
chloroform? (3 pts)
CH3CH2OH or C2H6O
HCl
CHCl3
A. 1 mole
C. 6x1023
D. 1.28 moles
Chloroform is mostly non-polar
and will not mix with the polar
ethanol/hydrochloric acid
mixture. What does polar
mean?
Spot test recipe calls for
1 mole acetaldehyde.
How many grams of
acetaldehyde is that?
One end of molecule is
+, other end -.
B. 16 grams
A. 44 grams
C. 32 grams
D. 29 grams
O
Visuals
Topic
Building Blocks
16. Fluoride (F-) in
high doses is lethal,
in low doses it is
used to fight tooth
decay.
The mineral in teeth is apatite
with formula: Ca?(PO4)3OH
How many Calciums are needed
to make this compound neutral?
Five
17. String theory tries to
unify all forces and all
matter. Even though it
requires 11 dimensions,
the math does explain all
forces and all known
particles.
Hoax & Myth Busters.
18. The Internet is full of
hoaxes and myths. Many
relate to chemistry.
Claim: A golfer who had
a habit of chewing on his
golf tee died after playing
4 rounds of golf. He died
from ingesting fungicide
sprayed on the grass by
chewing on the golf tee.
Status: TRUE
What does the string theory say
is the smallest building block
that makes everything in the
universe?
Extremely small strings
of energy
Below is the structure of the
fungicide he died from. If
someone burned this fungicide,
could hydrogen cyanide [HCN]
and hydrochloric acid [HCl] be
products of this burning (assume
hydrogen could come from
moisture in the air)?
Forces & Energy
Acids attack the OH in apatite
turning the OH to H2O. The
apatite is left with +1 charge.
How will water respond?
What are the 4 forces of the
universe? 5pts
Gravity
Electromagnetic Force
Strong Nuclear Force
Weak Nuclear Force
Electromagnetic force is said to
be 1036 times stronger than
gravitational force. How many
times would you have to say
billion to equal this?
4 times
And which one holds the
nucleus of atoms together?
Electromagnetic force.
Carbon & nitrogen are bonded in
the molecule by sharing 3
electrons each. Nitrogen has
one pair of electrons not
involved. Which would be
attracted to this pair of electrons,
acid [H+} or base [OH-]?
C N
A liter of diet soda has 500 mg
of aspartame. 1/10 of the
aspartame will decompose into
methanol. EPA set daily dose of
0.5 mg per kg body weight for
methanol. I weigh 100 kg. What
is my limit for methanol?
50 mg.
If I drink 2 liters of diet soda, do I
go over that limit?
..
…
19. List 3 myth-urban legend-hoax buster Websites:3pts www.snopes.com
Prescription fluoride toothpaste
is 0.4% wt/vol fluoride. How
many grams of fluoride in 1 liter
(about 10 tubes)?
Negative end of water will 4 grams.
be attracted and pull apatite Will it kill you if lethal dose is 5
grams? No.
apart
H+
Yes.
Mathematics
unpaired
www.hoaxbusters.ciac.org
Yes.
www.greenfacts.org