Michael Benichou
9/9/08
Chemistry
What has to do with water?
1. hydration-drinking
2. plant growth- watering plants
3. molecular development
4. one of the necessities for life
5. laundry
6. swimming
7. showering
8. washing dishes
9. washing car
10. cleaning
11. marine life
12. brushing teeth
13. waterfalls
14. wells
15. rain
16. hydro-energy
17. control
18. perspiration
19. oxygen
20. clear
21. solvent
22. fire hydrants
23. hydrogen
24. polar
25. adhesion
26. cohesion
27. makes up more than 2/3 of human body
28. can be solid, liquid, or gas
Indirect water use: - you don’t realize your using water
Can juice (1.3L)
+/- 120L H2O
One fried egg
450L H2O
- Chicken
- Drinks H2O
Direct water use - you realize your using it:
Putting water in a pot to boil pasta
Michael Benichou
9/12/08
Water:
70% of earth w/ water
Water cycle or Hydrologic Cycle
Rainfall, evaporation, (form clouds), condensation
pg. 17 ex. 1-3
1. a. Steam/electric
b. Steam/electric
c. Steam/ electric
d. Irrigation/agricultural
e. Mining
f. Irrigation/agricultural
2. In the East water is mostly used for electricity and the West uses most their water for
agriculture. Most of the nation’s farms are located in the East. Where the industries are.
In the West it’s mostly farms and agriculture.
Most fresh waters are from glaciers
Ogallala Aquifer
 largest in the World
 formed by glaciers 12,000 years ago
 Supplies 1/3 of groundwater used in the US.
 Water has been withdrawn 10-40 times faster than it’s replaced
 Dropped by 100 ft.
 22% for industry
 8% for homes and municipal use
 70% of withdrawals from rivers and ground water are used for agriculture
Michael Benichou
9/18/08
pg. 22
1.
2.
3.
4.
Watering plants, Washing cars, and baths.
I could not do without flushing toilets.
I could reduce water usage for showers by spending less time in there.
a. Use water from your bath when you’re done and wash your car with it.
Metric System:
SI units: International System of Units
Five units commonly used by chemists.
1. Meters
Length
2. Kilograms Mass
3. Kelvin
Temperature
4. Second
Time
5. Mole
Amount of substance
m
ka
k
s
mol
[6.02x 10 to the 23rd]
1. 356----3.56x 10 to the 2nd
2. 3.67 x 10 to the -5 -------0.0000367
3. 3.40 x 10 to the 4th------34,000
mega, kilo, hecto, deka---Base Unit---deci, centi, milli, micro, nano, pico
If you go from a higher # to smaller number than you multiply, small to big is divide
Mega-kilo=1,000 milli-micro=1,000 micro-nano= 1,000 nano-pico = 1,000
125 mg = .000125 kg
Michael Benichou
9/19/08
Matter:
Is anything that occupies space and has mass.
Physical Properties: Properties that can be measured and observed.
Physical properties of H2O : 1. Density 2. pH level (7) 3. clear 4. liquid-solid-gas 5.
boiling point 100 degrees Celsius 6. freezing point 0 degrees C 7. tasteless 8. odorless
9. colorless
For solid and liquid water doesn’t apply to this:
Solid: Densist state , very close to each other, doesn’t occupy every place, vibrates
Liquid: moving and not so close
Gas: Vibrating a lot, occupies everywhere, molecules collide
Only in water does solid occupy more room than liquid
Water as a solid is less dense than its liquid state.
Michael Benichou
9/22/08
Density of water is 1 g/ml or 1g/cm cubed
Cm.cubed = 1 ml
Dm.cubed = 1 L
Diet coke is less than I gram per ml. because it floats and its aspertane(fake sugar) has to
do with density.
Denisty= mass/ volume
(mass over volumer)
Can of soda has a mass of 150g. and a volume of 133 ml. What is it’s density?
150 g._
133 ml = 1.13 9/ml or 9/cm cubed.
Density of unknown metal is 2.8 g /cm3
Mass= 45g. What volume does it occupy?
45g.__
Xcm3 = 2.8 g./cm3
Multiply x to both sides then divide 45 by 2.8 and x=19.57 cm3
Michael Benichou
9/23/08
Significant figures:
1. Zeros between other non zero digits are significant
50.3 = 3 significant figures
3.0025 = 5 significant figures
2. Zeros in front of nonzero digits are not significant
0.892 = 3 significant figures
0.0008 = 1 significant figures
3. Zeros that are at the end of a number and also to the light of a decimal are
significant
57.00 = 4 significant figures
2.000000 = 7 significant figures
Floor: 7.7 meters by 5.4 meters
= 41.58 m2 = 42 m2
Michael Benichou
9/24/08
Do Now:
How many significant figures?
a.
b.
c.
d.
0.04450---4 significant
5.0003----5 significant
1.000 x 10 to the 5th ---Only first part, not power #---4
0.00002--- 1 significant (only last)----2 x 10 to the -5th
7.7cm x 5.4cm=41.53 cm squared
matter:
 anything that has mass and occupies space.
Michael Benichou
9/25/08
cm cubed is one mL- milli Liter
matter:
 2 categorie:
Heterogeneous
o Substances- must be pure
 Elements- one type of atom
 Compounds- two or more types of atoms
o Mixtures- two or more substances combined.
 Heterogeneous- Is not uniform
 Suspension: - Big paricles, - settle over time
 Colloid: - small particles, -cloudy; - not settle over time
 Homogeneous- Uniform; -- solution clear
 Solution:
o Solvent: Highest quantity of.
o Solute: Lowest quantity of.
Do Now:
Salad dressing- suspension
Yogurt- colloid
Oil based paint- suspension (anything you mix by hand is suspension)
Coca cola- homogeneous
Mayonnaise- colloid
Ocean water- heterogeneous
Distilled water- substance
Homogeneous
Michael Benichou
9/26/08
chemical symbol- Ex: H- hydrogen
chemical formula’s- represent substances or elements—ex: H20 (compound)
(2) subscript- how many
atoms of this element.
Michael Benichou
10/2/08
Co is cobalt
and CO is a compound of Carbon and Oxygen
Diatomic- pairs with itself:
N2, O2, Cl 2, I2, F2, Br2, H2
reactants
Chemical equations:
2 H2(g) + O2(g)
Reactants
H
O
2 H2O (g)
products
Coefficient: how many molecules.
(g) gas
(l) liquid
(s) solid
Protons = (+) p+
Electrons = (-) e-
Products
Neutrons = 0 n0
Atomic number represents how many protons
Na is 11 means 11 protons which means 11 electrons b/c an atom is always neutral.
Na + protons=11
Electrons = 10
Charge is +1
Cl- p+ 17
e- 18
Michael Benichou
10/6/08
atom= non charged particle
ion= charged particle
A positively charged ion is a called a Cation
A negatively charged ion is called a Anion.
Write CAtion first and Anion last.
Ionic compound =neutral
Ex: Ionic Bond: NaCl—Ionic Compound
This is why it’s NaCl and not ClNa, Cations first.
Michael Benichou
10/23/08
In summery of lab write what you learned,…
Pure and impure water.
Only H2O
H2O +
We do not neccessarily obtain pure water through distillation b/c of the air.
Air is O2, N2, CO2
Pg.46:
3.
1.
2.
3.
4.
5.
What land animals live near the river?
Was the river suitable for swimming?
Are commercial boats allowed to be on the river?
Is there any history of chemical dumping in this river?
Are there any plant damage from the affected?
4.
1. It is unlikely that it would be an oil-spill because oil on water forms a top layer
which would be seen.
2. Unlikely it’s acid rain because no other towns were affected and RIverwood is a
small town.
Michael Benichou
10/29/08
pg. 56
1a. 106 grams
b. 45 grams
2a. 21 grams
b. 56 grams
3. 56 grams
3a. 67
Unsaturated- a solution that contains less dissolved solute than the max amount (you can
add more solute and it will dissolve)
Saturated- max amount of solute is dissolved
Supersaturated- More solute dissolved than the max amount
Solubility- The max amount of solute that will dissolve in a certain quantity of H20 at a
specific temperature
 Depends on temperature, pressure, stirring (agitation), surface area
To find out if a substance is saturated supersaturated or unsaturated is by adding more
solute. You first shake it to see if its supersaturated. Then you add if it dissolves then it
unsaturated. If it stays a precipite in the beaker it is a saturated. If it you add and it
crystallizes then it is supersaturated.
Michael Benichou
10/30/08
EN- Some elements have a stronger attraction to electrons.- Electronegativity.-Ability to
attract electrons. Ϭ—slightly charged
Michael Benichou
11/5/08
water is a polar molecule. Which means there is a difference in electronegativity. Oxygen
is slightly negatively charged and Hydrogen is slightly positively charged.
Only able to create supersaturated by increasing temperatures.
Concentration: Could do either by percentage(most common) or ppb,ppb
Mass of solute/mass of solution X 100= __%
Ex. 17=solute 183=solvent 17+183=200(solution)
Ppm
parts mer million:
Mass solute
Mass solution X 1,000,000= ____ppm
Ppb
parts per billion
Mass solute
Mass solution X 1,000,000,000 = ___ppb
17/200 X 100 = 8.5%
Michael Benichou
11/10/08
Why are nitrates good.
Test is on 1-87 and metric system
No significant measures on test.
Bring Calculaters
Topics:
All chemistry concepts- physical properties, chemical properties, mixtures,
END OF 1ST QUARTER
Michael Benichou
11/14/08
Unit 2:
Properties:
Physical and chemical properties
Physical properties: can be observed or measured without changing the substance
Reversible.
Phase change (l g) (s-g) color. odor. Density. Boiling and freezing points.
Chemical: when the substance changes into a new substance.
Non-reversible
Any chemical reaction.. oxidation, combustion,…
Michael Benichou
11/18/08
1800’s 60 elements
Mendel arranged it by—
-atomic masses
- ability to react- With oxygen(some elements
oxidize very fast and some not at all, like Noble
Gases have no reaction and other side reacts
with oxygen very fast.) x- any element
EX: XO3 XO2 X 2O XO
With Chlorine
Michael Benichou
11/20/08
Sodium chloride is held together by bonds that result from attraction of ions.
In testing water for ions, a reference solution is used to show what happens when the ion
is present in the test.
When potassium thiocyanate (KSCN) solution is added to a solution that has dissolved
Fe3+ ions react with SCN- forming colored ions.
In water treatment plants, chlorine is added to source water to kill harmful bacteria. IN
the U.S., the maximum amount of chlorine that may remain in drinking water is 0.0004
grams per 1,000 grams of water. What is the maximum amount of chlorine that may
remain in drinking water expressed in parts per million (ppm)?
A polyatomic ion is an ion containing many atoms.
Water is a polar molecule so it can break up ionic compounds which is why for ex:
KNO3 would dissolve in water.
Which sample represents a homogeneous mixture( it is something like is mixed- a liquid)
so CO2(aq) would be the answer. Aquous means it’s a water based solution.
Michael Benichou
11/25/08
Periodic table is called “periodic” because there are patterns of properties with each
columns.
Halogens are ditomoic they bond with themselves. It’s just a family name.
Alkali Group 1- are extremely reactive.
Earth Alkaline Metals, Group 2- fairly reactive. When something is alkaline they’re
slightly basic.
Halogen, Group 17- Mostly are in gaseous state each have a very specific color.
Noble Gases, Group 18- Very stable, gases
Atomic mass= #neutrons + #protons
Electron 1/2000 the mass of a proton or neutron.
25
17 Cl bottom one is protons and top is atomic mass.
Isotopes- same elements with same amount of protons, but a different amount of neutrons.
(have different mases)
Michael Benichou
11/26/08
there was once an element when the periodic table was being compiled he saw that there
was an element missing under si and in between Se33 and As31 and so he called it ekasillicon. Same group has the same chemical properties not necessarily the same physical
properties. And so the physical properties are in a pattern by the rows. Like here ekasillicon would have a boiling point in between As and Se.
Metals are located on the left side with the exception of hydrogen. Right side is nonmetals. In staircase every element above and below it except for aluminum is a metalloid.
Michael Benichou
12/1/08 & 12/2/08
Quantum mechanic model:
n represents an energy level. n= each energy level is given a principal quantum number n.
lowest energy=1 the further away from the nucleus the higher the energy. The closer the
n the lower the amount of energy. Ex: n1 has the most comfortable and least energy since
it’s closest. Then come n2, n3, n4.
First n level is 2e-, 8e-, 18e-, 32e-.
Chemical Properties of an element depend on the # of e- in the outer energy level of it’s
atom called, Valance Electrons.
Each energy level contains: sublevels- 4 sublevels called, s, p, d, f.
Orbitals, a location inside the atom where the e- is most likely found.
Each orbital can have a maximum of 2 e-.
1 orbital: s-orbital (round shape- O) maximum of 2 e3 orbitals: p-orbital Px, Py, Pz
maximum of 6 e5 orbitals: d
maximum of 10 e7 orbitals: f
maximum of 14 e4Be
= 1 S2 , 2S2 (- electron configuration)
F – 9 electrons - 1S2 2S2 2P5 most likely will be very reactive b/c it’s missing just one
e- to be stable . F will become negative
Na- 11 electrons- 1S2 2S2 2P6 3S1
positive.
Na will most likely give up one making it the
Ne- 10 electrons- 1S2 2S2 2P6
Cl- 17 electrons- 1S2 2S2 2P6 3S2 3P5
Write the electron configuration for the following:
-nickel : 28Ni : 1S2 2S2 2P6 3S2 3P6 3D10
-sillicon : 14 Si: 1S2 2S2 2P6 3S2 3P2
-potassium : 19K: 1S2 2S2 2P6 3S2 3P6 3D1
-potassium as an ion: It will become + because just as Sodium gives up one and is
positive so should this.
Michael Benichou
12/3/08
Orbital notation- tells how electrons are oriented
Ex. 6C – 1S2, 2S2 2P2
2 electrons per orbital.
Michael Benichou
12/4/08
ground state: all the electrons in this atom valance e- occupy the lowest possible energy
levels.
When an electron goes up an energy level and then goes down again it makes energy
which is called photon which is light.
Michael Benichou
12/8/08
RadiusGroup: H. 1S1
Li. 2S1
Na 3S1
K 4S1
When electrons are on a higher nuclear level they are more apart than the positive
charges
Radius increases as you go further down the group.
As you move further down the period
the radius decreases. b/c you have an
increase of electrons in the outer shells and therefore the attraction is stronger. So the
Noble gases have very close electrons because they have full outer levels.
The first energy level is attracted to the nucleus, but the 2nd energy level repels from the
first b/c they are 2 negative charges.
Michael Benichou
12/16/08
L(losing)E(electrons)O(oxidation) says G(gaining)E(electrons)R(reduction)
LEO says GER
Each one (reduction and oxidation) are half reactions
Both together which is the only is called Redox.- means transfer of electrons
Both processes happen at the same time
Zn + Cu2+
Zn2+ + Cu – full Redox reaction
Michael Benichou
12/18/08
molar mass: mass of one mole g/mol
1 mole of Fe= 55.845 g
(6.02 x 1023 atoms of Fe)
2nd Semester
Michael Benichou
2/3/09
Organic Chemistry – particles coming from living things
(aka- Chemistry of Carbon)
Petroleum:
Fractional Destilation- boiling the oil to separate the substances inside
Organic chemistry: chemistry of carbon—hydrogen.
Boiling point is a specific for one substance—100 degrees Celcius
Boiling range can be more or less than the point. 100 degrees C. – 150 degrees celcius
Michael Benichou
2/11/09
Isomer = Same molecular formula different structure.
Michael Benichou
2/17/09
solid state the molecules are very close to each other. Vibrate but don’t really move.
Liquid state- more space in between molecules
Gas state- a lot of spaces in between molecules, particles move really fast.
To get from liquid to gas you heat(add energy) if intermolecular forces are very strong
you need more energy which means you have a higher boiling point.
Naming Alkanes (Nomenclature)IUPAC( International Union of Pure and Applied Chemistry)1) find the longest continuous chain of carbons (parent chain)
2) Name the parent chain ex. …….. hexane
3) Name the side branches.
Ex. CH3 - methyl
CH2-CH3 -ethyl
Alkyl groups
CH2-CH2-CH3 -propyl
4) Precede each alkyl group name with a prefix indicating how many there
are present.
If 1 – no prefix 2- di 3- tri
5) Designate the position of each alkyl group on the parent carbon chain by
number.
Michael Benichou
2/19/09
Hydrogenbonds- Water has a such a high boiling point
Fossil fuels: Bio-molecules of prehistoric planet and animals
Ex: petroleum, natural gas, and coal. (nonrenewable)
Fuel---energy -- we can use it
Potential energy: energy of position ; energy of storage ex. a plate of food
Kinetic energy: energy of motion ex. when I’m actually walking
Crude oil is potential energy and once you burn it, it is kinetic energy. Burning the fuel
the energy that is released is then used.
Reactants --- products
Chemical bonds have potential energy stored
Fuel is valuable because we can release the energy and then use it.
CH4 + 2O2 (bond breaking-costs energy) --- CO2 + H2O + energy (the forming of new
bonds-releases energy) = a full combustion (the burning) makes all these products
Combustion always has energy as a product- can be felt by heat from a fire
Exothermic= releases energy, energy is written as a product.
Endothermic= costs energy, energy is required; energy is written as a reactant
Potential energy diagram- shows that reactants have more energy than the products
The change in energy is called delta H—change in enthalpy
Reactants--- products + energy
Michael Benichou
2/26/09
Thermo chemistry
Heat (q) : Energy that transfers from one object to another because of a temperature
difference between them. Will always flow from a higher temperature to a lower
temperature.
Law of Conservation of Energy:
In any chemical or physical process, energy is neither created nor destroyed.
System + Surroundings
Ex. the heat pack is the system and the heat dispersing outside is the surroundings.
Endothermic reaction- Heat flows from surroundings to system. Heat absorbed by system.
Exothermic process- When heat is released to its surroundings. System
Surroundings
Symbol of heat is q.
Exothermic reaction- q has a negative value b/c it’s leaving the system. Product.
Endothermic reaction: q is a positive value b/c its being absorbed by the system. Reactant.
Unit heat(q) = Joule –SI unit [or calorie]
1 dietary Calorie = 1000 (scientific) calories
4.184 J = 1 cal
Heat capacity: the amount of heat needed to increase the temperature of an object exactly
1ͦ C
Depends on: mass + chemical composition
Specific Heat capacity: amount of heat it takes to raise the temperature of 1 gram of
substance 1ͦ C.
Specific heat capacity for water. 4.2 J / g ͦ C
For iron. 0.46 J/ g. ͦ C
Calculating specific heat:
q___________
C= m times delta T
C= specific heat
Q= heat (Joules)
M= mass (g)
Delta T = Change in temp ( delta T =Tf – Ti = ͦ C)
When 435 J of heat is added to 3.4 g of olive oil at 21 ͦ C, the temperature increase to 85 ͦ
C
What is the specific heat of the olive oil?
___q___
__435 J__
C= m x delta T
C= 3.4 g x 64 ͦ C
C= 1.99 J/g. ͦ C
Michael Benichou
3/3/09
Heat of Combustion :
The quantity of thermal energy given off when a certain amount of substance burns.
Molar heat of combustion:
The quantity of thermal energy given off when one mole of a substance burns.
CH4 + 2O2
CO2 + 2H2O + heat (-- _?_k)
Heat of combustion for methane = 55.6 kj/g
Molar heat of combustion for methane = 890 kj/mol
CH4 + 2O2
CO2 + 2H2O + 890 kj
Delta H= -890 kj ( negative since it’s exothermic- b/c it’s in the prodcts)
Delta H = change in enthalpy (basically the change in energy)
Find heat f combustion for paraffin
Michael Benichou
3/5/09
heat of combustion = amount of energy released per one gram.
Heat in changes of state:
If we have a phase change from a liquid to a gas the temperature doesn’t change.
Michael Benichou
3/9/09
molar heat of fusion: the heat absorbed by one mole of a solid substance as it’s melts to a
liquid at constant temperature.
Delta H of fusion = negative delta H solid
Water (s) --- water (l)
Water (l) --- water (s)
delta H of fusion 6.01 kJ/mol
delta H solid = -6.01 kJ/mol
Going from a liquid to a gas its delta H vaporization
Molar heat of vaporization: the amount of energy needed to vaporize one mole of a given
liquid
Requires less energy to melt a bowl of ice than to vaporize a bowl of water
Delta Hvap = -- delta Hcond.
Water (l) --- water (g) delta Hvap =40.7 kJ/mol
Water (g) --- water (l) delta Hcond. = --40.7 kJ/mol
How many grams of ice at 0oC will melt if 2.25 kJ are added?
Delta H fus
6.01 kJ = 2.25 kJ
1 mol
x
18 g/mol
x= .37 mol
x 0.37 mol = 6.74 grams
ex. How much heat (in kJ) is absorbed when 24.8 g. water (l) at 100oC and 101.3
kPa[STP, standard pressure] converted to steam.
40.7 kJ = X kJ
18 g
24.8 g
x= 10.96 kJ
Michael Benichou
3/12/09
Petrochemicals: compounds produced from oil or natural gas.
Polymers: Large molecules composed of 500 to 20,000 repeating units called monomers.
Ex. any kind of plastic; nylon fabric.
Michael Benichou
3/16/09
Hydrocarbons:
Alkanes: contain single bonded covalent bonds
HH
l l
Ex.
Ethane:
H-C-C-H
C2H6 CnH2n+2
l l
HH
Alkenes
Double covalent bonds – one of them can break and react with another
compound- an addition reaction: you’re adding something to it.
Michael Benichou
3/18/09
alkanes are considered saturated hydrocarbons because they all have single bonds[only
single bonds] double and triple bonds are unstable and reactive- alkene & alkyne and
those two are unsaturated hydrocarbons.
It can go from a saturated to an unsaturated.
If ethanols are added [x amount] then it becomes a polymer.
2 ethenes are added form a polymer we can choose to represent a little part of the
polymer or representing it in a shorter way.
4th Quarter
Michael Benichou
3/20/09
linear polymers are flexible- a chain of monomers-polymer (no branches)
branched polymers – they can have side branches and are usually smaller
Cross linked- if you have two polymers(branched or linear) and it gets rid of its flexibility
to move. Sturdy polymers. You can get rid of cross linked and then becomes a mush of
what it is w/o the connection
A polymer can be formed by other alkenes or alkynes: ethane, propene, butene (there are
2 ways to draw butene though [1 &2]
A double bond is a functional group and has higher priority than a branch so you start the
numbering by the side of the double bond not the side branch.
Michael Benichou
3/23/09
Cyclic Hydrocarbons:
Ex. cyclohexane
Acids are proton donors- they donate H+
Carboxylic Acids give out H+’s
Esterification- the forming of esters
Catalysts speed up reactions
Michael Benichou
3/31/09
gases laws
1)
2)
3)
4)
5)
6)
Boyle’s Law
Charles’ Law
Guy Lussac Law
Avogadro’s Law
Yoleal gas law
Dalton’s Law
Pressure: P= Force/Area = N/m2
Measure a force using Newtons –N m2- meters squared way to measure the distance
Atm- atmosphere
P= 1 atm ground level
mmHg- millimeters of mercury (a measuring unit for pressure)
P= 1 atm =760 mmHg
P= 2 atm = 1520
2 atm (760 mmHg)
( 1 atm
)
1 atm= 760 torr
1 atm= 760 mmHg
1 atm= 101.3 KPa (Kilo Pascal)
Temperature= Kelvin= Co + 273
V[volume]= L[liters]
1 L = 1000 mL
D = density = mass/volume = grams/Liters
Solid - density=gram/cm3
Liquid – density=grams/ mL
Gas – density = gas/Liters
Michael Benichou
4/6/09
Air has mass; air takes up space.
Pressure exerted in all directions; pressure comes from air and water
Units of pressure: molecular collisions against wall of container
1 atm = 760 mmHg = 760 torr = 101.3 kPa
Units of temperature: Kelvin
K = oC + 273
Units of volume: usually liters ( L, mL, etc.)
Boyles Law: [P1V1=K(constant) 1 atm x 700mL = 700mL x atm]
P1V1 = P2V2
2 atm x 350mL = 700mL x atm
1 atm x 700mL = 2 atm x V2
2 atm
2 atm
350 mL = V2
As volume decreases, pressure increases; (As volume increases, pressure decreases)
When you bring a bag of chips up on a plane the bag gets bigger but when you land it
gets smaller again.
Going up pressure decreases but when you go down pressure increases.
It has a relationship that when you have something you double the answer causing an
exponential descent and not a straight line going downward
Charles’ Law:
T1/V1 = T2/V2
T/V = K
293K/ 1L = k
586K/2L = k
As temperature increases, the volume increases; as the temperature decreases the volume
decreases.
Michael Benichou
4/21/09
Volume of gas defined by container
Partial Pressure- Dalton’s Law
P = 2 atm
Ptotal = 2 atm
Ptotal = Pblack + Pred
Pblack= Xblack x Ptotal
Pred = Xred x Ptotal
Pred = Xred x Ptotal
Pred = .5 x Ptotal
= 1 atm
Xred = # moles red / # moles total
.5 = .5 mol red/ 1 mol
Ptotal = 658
PN2 / Ptotal = 325 torr/ 658 torr
XN2 = .5
Michael Benichou
4/23/09
When volume is constant, what happens when temperature is increased ? Pressure
increases and there are many more collisions T1/ P1 = T2/ P2 - Gay-Lussac’s Law