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Monday, June 6, 2011

Organic Chemistry Fuctional Groups

Organics Compounds can contain elements other than C and H

Some examples of fuctional groups are: Alcohols, Halides, Aldehydes, Ketones, Carboxylic Acids, ethers, Amines, amides, and esthers.

Halides and Nitro CompoundsThey are named similar to simple hydrocarbons and can be attracted to alkanes, alkenes, and alkynes.
The main chain will recieve prefixes
*di-, tri-, tetra-, in front for multiple groups

Halogens                 Nitro                       *memorize these*
F = fluoro               N02 = nitro
Cl = chloro
Br = bromo
I = Iodo


Halogenated Compounds
1. Compounds with F,Cl,Bri,I are generally insoluble
2. Fluorinated hydrocarbons are unreactinve
3. Cl and Br are more raective, but only under conditions
4. I are very reactive. The iodide atom can be easily replaced by other functional group.

Properties of Nitro Compounds

1. Normally insoluble in water
2. Unreactive to chemical attack, except under drastic conditions
3. They tend to be explosive such as TNT
4. Pleasant odour.

Alcohols-organic compounds that contains an -OH (hydroxl)
Named By...

using the longest Carbon chain containing OH group.
Replacing the E in the parent hydrocarbon with -OL

Alcohol chains has lowest possible number

Properties of Alcohols
1.Hydroxl group tends to make it soluble. But the hyddrocarbon makes it insoluble
2.All alcohols are poisonous to some degree (ethanol is in alcoholic beverages)

Multiple -OH
If a compound has more than one group, number them both and add the ending -diol, -triol, etc.

Aldehydes
are compounds that have a double bonded oxygen
and they follow standard rules (-al)
-Methanol

Ketones
a ketone is a hydrocarbon with a double bonded oxygen that is not on either end.
and they apply standard rules

1.Both are partially soluble
2.Aldehydes are very reactive and they are esily converted or oxidized
3. Ketones are relatively unreactive.

For more help and examples, check out these sources.



http://www.chemistry-drills.com/functional-groups.php?q=simple

Alkenes and Alkynes

Carbon can from single, double, and triple bonds with Carbon atoms.
The position of the double/triple bonds always has the lowest number and it is in front of the parent chain.

Alkane - single bond
Alkene - double bond
Alkyne - triple bond

Alkenes are hydrocarbons with one or moer double bonds (unsaturated(
They end in -ene from -ane
 E.g  CH3 - CH2- C - CH - CH3                         3ethyl-2pentene
                       |                  -

                    CH2 - CH3

There are also things called Geometric Isomers which are only used in Alkenes. They have the same formula but in different arrangements.

Trans/Cis

*note* This is only used for alkenes.

Trans is used when the CH3 and H3C is on opposite sides (diagonal)
Cis is used when you have CH3 and H3C on the same ( top/top, bottom/bottom)

Alkynes are carbons with 3 or more triple bonds
when naming them you change the ending from -ane and -ene to -yne

Here's a video with more examples

Tuesday, May 31, 2011

yea its blog time cool...

Alkenes and Alkynes hmm

if you wonder what it is then to bad don't read this because i don't know either. ... I'm just a random person doing a random blog.... yay.. fun...
OKAY.

alkene is double bone that a carbon form and a alkyne is a triple bond that carbon form basicly that's all...
yea please read other people's blog if you want more information....

okay ALL OF ALKENE AND ALKYNE ARE NOT SATURATED

sigh I'll probably fail with just that so time to make up some more stuff.
first of all for a double/tri bond it always have to be the lowest number so if there are 5 c and the bond is at from left second it won't be 4 pentene but it would be 2 pentene don't ask why because it life

C= C C C C
the H aren't there because im lazy

so we will start with alkene first. for alkene in another words double bond just change the ending from ane to ene. yes that it. not more. its as easy as 1 2 3. OMG I HAVE A QUESTION A VERY SMART STUDENT ASKS SO IT WOULD BE METHENE? NO because how can you have a double with just 1 carbon = = (i the teacher think the student isn't the smartest)
yea so methene won't work but the rest does... butene ethene propene pentaconten
okay so naming FIND THE LONGEST CONTINUES CHAIN and then PUT THE DOUBLE BOND AT THE LOWEST NUMBER AND NO 6 IS NOT LOWER THAN 2. - - IF THE NUMBER IS BIGGER THAN THE NUMBER OF CARBON IN THE LONGEST CHAIN SOMETHING IS WRONG!!!!! I RAGEEEEE!! RAWR!! also change the ending to ene that's all everything else is basically the same with alkane. THERE IS CIS AND TRANS STUFF HERE

H3C CH2 CH2 CH = CH CH3
2-hexene
there example

this makes absolutely no sense
okay Alkyne now.. OMG ITS THE SAME EXECPT IT TRIPLE AND NOT DOUBLE OMG OMG OMG CHANGE ITS ENDING FROM ANE TO YNE SOOOO CREATIVE  O YEA one other thing is there is no cis or trans for triple bond




as always youtube and some random places
okay she has weird accent lol but it pretty detailed

Monday, May 30, 2011

Organic Chemistry

this is what you have to remember.ending will change when it is not an alkane

well this thing called organic chem iono wat it is but i believe that this piece of organic is all about carbon compounds.  These compounds all have low melting points, non electrolytes and THEY CAN FORM SUPER COOL LOOKING CHAINS!!! Like omg i have NEVER seen anything so pro before. Its like art.  They can form something called a straight line, circular pattern or branched pattern.  The carbons are also supposedly pro since they can form single, double, and triple bonds.  Also characterized by one line, 2 lines or 3 lines. cool.  o yea also know that a hydrocarbon is a compound that contains both hydrogen and carbon this is someting YOU MUST REMEMBER. ok now onto other stuff you must remember. Also know that a saturated hydrocarbon means it is not possible for another atom to combine to the current chain. Unsaturated is the opposite.

here is the list of alkanes and their molecular formula.  The root of the words will be the same but the ending will change according to what you are naming so yes this is important


an alkyl also known as R is an alkane which lost 1 hydrogen.  you can find out what is an alkyl group because it is usually the left over parts of the structure. after you find a chain of the carbons, the structure left is the alkyl group.

Thursday, May 19, 2011

Chemical Bonding

What is chemical bonding? I would say that it is the bonding of chemicals. WHAT? REALLY? OMG REVELATION.

NOTEWORTHY:
only valence electrons involved b/c they want to make a full shell

In junior science, it was taught that there were only two forms of bonds. Ionic and Covalent. WRONG
THERE ARE TWO PLUS A SUB DIVISION OF ONE OF THEM. *GASP*

Ionic Bonds
electrons transfered ie. GIVE ME ALL YOUR ELECTRONS FOOL
Non-Polar Covalent Bonds
electrons are shared equally ie. SHARING IS CARING, LETS SHARE TOGETHER
Polar Covalent Bonds
electrons are shared unequally ie. MOM TOLD ME WE HAD TO SHARE SO TAKE THIS

How do bonds come to be? Electrostatic Force acts on subatomic particles. Like charges repel, opposites attract. Cool? cool.

Ionic Bonds
-electrons transferred from metal to non-metal
-metal forms positive ion(cation) bc loses electrons
-non-metal forms negative ion(anion) bc gains electrons

Ionic bond of Na and Cl to form NaCl
As we can see, the lone electron from Na is transferred to Cl. Both acquire full valence shells and become more stable. Since they both have charges opposite to each other after the reaction, they are then attracted to each other in a bond.

Electronegativity
This is how much atoms want to gain electrons. If we measure the electronegativity from two different atoms, we can determine what kind of bond they will form with the difference in absolute value.
enegdiff = Math.Abs(eneg1 - eneg2);

if (enegdiff < 0.5){
      bondtype = nonpolarcovalent;
}
if (enegdiff >0.5 && enegdiff< 1.8){
      bondtype = polarcovalent;
}
if (enegdiff >1.8){
      bondtype = ionic;
}

Non-polar Covalent
electrons shared equally due to octet rule
bonds formed are IMPECCABLY STRONG
this would lead you to think that they have very high melting points but for some this is not the case

Molecules are held by Intermolecular forces, which are WEAK. During the boiling process, the bonds themselves may not give, but the weaker intermolecular forces will.

electrons equally shared in the centre


 Before we continue:
Polar ---> opposite charges on opposite sides of the bond
NonPolar ---> both sides equal in charge

Polar Covalent
One atom will have significantly more electronegativity than the other, therefore, electrons will spend time in one atom more than another. This will create poles on either side of the bond because one atom will be slightly more negative and the other slightly more positive.

If the atom has higher electronegativity ---> partial negative betw. 0 to -1
If the atom has lower electronegativity ---> partial positive betw. 0 to +1
for Ionic bond: higher electronegativity ---> atom forms cation
                       lower electronegativity ---> atom forms anion

Observe the above picture. The arrows represent which way the electrons are migrating due to the polarity
The little hook symbols represent the partial charge on either side of the polar bond. Dipole attraction refers to the attractive force between the negative end of one polar bond to the positive end of another polar bond.

Kthnxbye

Wednesday, May 4, 2011

Periodic Trends

There are many trends within the periodic table whether it is in groups, left right up down or w.e. Here are some of the following

Elements are more metallic as they go down in a family and all the metals are grouped on the left while all the non metals are on the right. The metalloids are in the middle

Atomic radius decreases going right in a period but increases going down a family. Going across a table also increases the atomic number aka protons.

Metals and nonmetals in reactivity is quite funny. When a metal goes down and right once it gets more reactive so if it goes up and left once it is getting less reactive. Nonmetals are opposite of this. Going up in a family increases its reactivity

Electronegativity is a measure of the attraction of an atom for the electron. The higher it is the more attraction it has to electrons. electronegativity decreases as atomic number increases.

Melting and boiling point. The elements near the centre of the table has the highest while noble gases have the lowest

ionization energy is the amount of energy needed to remove 1 electron because it is a noob and not needed. Ion. Energy is increases moving left to right in a period and decreases moving down a family.

Thursday, April 21, 2011

Electron configuration... yes boring title i agree too...

silicon is 1s22s22p63s23p2

DOES THAT MAKE ANY SENSE TO YOU?
IF NOT PLEASE CALL 1-800-NED-CHEM THERE YOU WILL GET ALL.
okay time to get REAL serious.

So what does this electron configuration mean? its basically how each electron is place in an atom.

So there are 2 numbers one is energy Level and the other is number of electrons in that energy level and orbital
Energy level is the number in the front "n" and the energy difference between 2 energy levels is called quantum of energy. COOOL quantum... = =.
now there is this thing called ground state and excited state.
ground mean its stable and will most likely not do some random explosion.
excited means its excited... imagine an excited person.. what will he/her? yea jump around and that is what the electron does too... it jumps.. to the lower shell to gain stability and become ground. In this process it releases energy..SO MUCH TALKING BORING...
Orbital = region of space used by an electron in an energy level s.p.d.f
Shell = a group that have the same orbital and n value the 1.2.3.4.5.6.7 # in the front
Subshell = the s p d f thing that are in the same shell like 1s 1p 1d 1f but they contain different numbers of electron
in n=1 shell there can only be s type
n=2 is s and p type
n=3 is s p d type
n=4 s p d f type

all s type subshell can have 1 s orbital
p have 3 p orbitals
d have 5 d orbitals
f have 7 f orbitals

and each orbital can have 2 electrons...
IN CONCLUSION
s subshell can have 2 electron
p have 6
d have 10
f have 14

Higher "n" number = less stability.. and = more energy release when it get excited and jump that's why the uuu stuff can only live for a millisecond

this is boring right?
i agree...

the order is 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p
7s 5f 6d 7p... BUT THAT IS LIKE NERD LEVEL MEMORIZATION
so normal people like me who isn't no-life science person use the
awesome graph of love



















and yes this is as easy as it gets.

Electron always fill from the lowest.. so THERE WILL ALWAYS BE 1 + electron in 1s if u don't have 1s something is wrong...
Also electrons likes to be by themselves instead of pairs... so ALWAYS ^ ^ ^ and then v v v (yes i know they are v's... to bad)
negative Ion just means its full shell it will be like the next noble gas easy yes
positive ion isn't so cool... if its +5 you have to take away 5 electrons and if there are electron in s and p orbitals p is removed first (plz don't ask why only some random chem nerd will be able to answer you that)

by this point you are probably wondering why I'm not finish yet... (yea i know life suck i got a long blog live and read plz, apparently we learned a lot today so too bad...)
Okay now Core notation
Core Notation = above row NOBLE GAS + Valance electron config and yes this makes your life easier... BUT the teacher can be mean and make you write Uranium and make you write in stander form lovely isn't it?

WE ARE ALMOST DONE

now we got 2 bad boys Cr and Cu they are bad because THEY START WITH C don't confuse with Cs which stands for counter strike or Cd... or Dy just because people aren't that smart these days

All ions and noble gas have full valence shells the + - sign on the atom means - means its needs w/e amount of electron
+ mean it needs to get rid of w/e amount of electrons
example Ag [Kr] 4d10 5s1 and Ag ion will be [Kr] 4d10

also there is this open and close shell thing...
open = not full still open...
close = to bad no more electron is accepted and is close for business.. = full shell...

Examples
U uranium?? electron config??? STANDER FORM YES I AM MEAN
okay i give u answer... just incase your teacher give u this...

1s2,2s2 2p6,3s2 3p6 3d10, 4s2 4p6 4d10, 5s2,5p6 5d10 5f3, 6s2 6p6 6d1, 7s2
this is torture mode
normal mode.. [Rn] 5f3 6d1 7s²... OMG SO MUCH SHORTER

okay Ga is next

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1
core is [Ar] 4s2 3d10 4p1
yea now its ion is since its +3 so you have to get rid of 3 electron and always start from p then to s so answer
[Ar] 3d10 too bad no stander form its happy so yay and stable..

like electron config can't really have really weird questions so just pick random element from periodic table and write the electron config.. REMEMBER CR CU!!! THEY = EVIL

always end with youtube yes

Tuesday, April 19, 2011

Atomic Structure

OK. Long story short: Theres this thing called an atom, inside are electrons and a nucleus. Inside the nucleus we have protons and neutrons.

k thanks for reading, bye.







































KIDDING!
OK SO.  Heres the general idea of what an atom looks like as we know today:
Atom ---> Electrons in orbitals in shells + 1 nucleus ----> protons and neutrons ----> quarks (we'll save that for another time)

ANYWHO.... lets start with our 3 main subatomic particles.
The Proton: Charge: +1, Mass: 1 amu or 1.672 * 10^-27 kg,
The Neutron: Charge: 0, Mass: 1 amu or 1.674 * 10^-27 kg
both of these particles are located within the nucleus. Though the neutron has a slighty larger mass, we still count it as 1 amu
The Electron: Charge: -1, Mass: 0 amu or 9.11 * 10^-31 kg
these particles are located in orbiting shells around the nucleus. The mass is deemed so small that we use a 0 amu.

NOW.. we move on to the different properties of atoms.
Atoms are either neutral of charged.
A neutral atom is said to have equal amounts of protons and electrons therefore balancing out the charge.
A charged atom is called an ion. It will have lower or higher amounts of electrons than protons
If there are more electrons, the atom is negatively charged and deemed an anion
If there are less electrons, it will be positively charged and deemed a cation

Mass Number:
This is the total mass of an atom in amu.
Calculated by # of protons + # of neutrons

Atomic Mass:
the average atomic mass of the different isotopes of an element
isotopes: elements have different masses depending on the number of neutrons they have
for example: uranium-235 and uranium 236. By adding 1 neutron to uranium-235, you'll get uranium-236. This turns a stable atom into an unstable atom that has the potential to create nuclear explosions.

The mass number and atomic mass are similar but not the same. When working with molar calculations, we usually refer to the atomic mass. BUT HOW TO FIND AVERAGE MOLAR MASS???? HMM???

ex. Hypothetical element X exists as 67.24% X-23 (23.251) and 32.76% X-24 (24.446). What is the average molar mass of hypothetical elemt X?

We simply average it out like so:

(0.6724)(23.251) + (0.3276)(24.446) = 23.64

Atomic Theory

Yay, atomic theory. What it is? I will tell you.

Atomic theory is a theory of the nature of the atom (Greek: atmos) which is the smallest pieces of matter
       Aristotle believed in the four elements: fire, water, earth and air
       Alchemists believed they could turn metal into gold


But this was not a scientific theory because it could not be proved with observation

One of the first greek philosphers who mentioned atoms was Democritus in 300 B.C. He thought that they were idivisible particles Hmm interesting.'



After Democritus, Lavoisier in the late 1700's introduced the Law of Conservatino of Mass and Definite Porportions



Next came Proust (1799) and he proved Lavoisiers' Laws by experiments.

Dalton came after in the 1800's and he stated that atoms are solid, indestructable spheres. Based on the Law of Conservation of Mass



There were still many things that werent discovered but later on in the 1850's J.J. Thomson discovered that atoms had positive and negative charges.



In 1905,  Rutherford shows that atoms have a positive, dense center with electrons and suggested that atoms are mostly empty space.



Neils Bohr (1885-1962), studied gaseous sample of atoms which were made to glow by passing through an electric current. He proposed that electrons surrounded the nucleus in specific "energy levels" or "shells."



This video below will show you a brief timeline of all the scienetists and people that are important. Yeah.



Monday, April 4, 2011

MOST ASWOME LESSON ON PERCENTAGE WHICH WE DIDN"T LEARN IN GRADE 2!!!!! FUN FUN FUN FUN FUN!!

life is like a sign sigh.
Yay after the long break we finally start learning again.. fun…..
Don’t have much time so Less random stuff sorry~ and of course we all still remember the super fun and exciting lab right?
Okay~ we are doing Percent Yield and Percent Purity
So what is Percent Yield and Percent Purity Percent yield is found by dividing the actual mass of product formed by the mass of the product expected hmm what does this mean? It means that Percent yield is how much stuff will be produced when 2 chemicals are reacted together so what percentage of thing is actually formed.
Percent Purity on the other hand is the percent of a specified compound or element in an impure sample. So out of the big chunk of rocks how much of it is actually useful? Only the useful stuff reacts.
Okie examples…
3Mg(OH)2 + 2H3PO4 H Mg3(PO4)2 + 6H2O
Q1 Calculate the mass of Mg3(PO4)2 that will be formed (100% yield) from the
reaction of 15.0 g of 92.5% Mg(OH)2 with an excess of H3PO4.
13.875g Mg(OH)2 * 1 mole Mg(OH)2/ 1 mole Mg(OH)2 * 1 mole Mg3(PO4) 2/ 3 moles Mg(OH)2 * 262.9 g Mg3(PO4)2/ 1 mole Mg3(PO4)2 = 20.9 g Mg3(PO4)2   (typing that took years)
Q2 Calculate the mass of 88.5% Mg(OH)2 needed to make 127 g of Mg3(PO4)2, assuming a
100% yield.
Gold ore
127 g Mg3(PO4)2 x1 mole Mg3(PO4)2 / 262.9 g Mg3(PO4)2 *  3 moles Mg(OH)2 / 1 mole Mg3(PO4)2  *  58.3 g Mg(OH)2 / 1 mole Mg(OH)2   = 84.49 g Mg(OH)2.

Okay Percent Yield Question
CaC03 ---> Ca0 + C02
If 50kg of Calcium carbonate is used, and 21kg of calcium oxide is made, what is the percentage yield of the reaction?
The reaction is OMG I don’t know how to do this…  Jokes…
50 kg CaCO3 x (1000 g CaCO3 / 1 kg CaCO3) x (1 mole CaCO3/ 100.09 g CaCO3) x (1 mole CaO / 1 mole CaCO3) / (56.08 g CaO / 1 mole CaO) x (1 kg CaO/ 1000 g CaO) = 28.015 kg CaO
Hahahah you see how the Kg part screwed everyone over? XD
21 kg / 28 kg = 75% yield



a chinese dude teaching win!

http://misterguch.brinkster.net/pra_equationworksheets.html

god level site for chemistry!

Wednesday, March 16, 2011

some lab thing..........you work with another pair......yay

ummm yea.....we had a lab....sooo fun.. 6D to be precise.  This experiment is unique in that it takes 2 days to do it.  The purpose of this is to determine which reactant is limiting and which is excess.

ok we wore our super cool stuff.  Then we obtained 2 reactants known as Na2Co3 and Cacl2.  We weighed them both and then  we combined them in a 25ml beaker and waited for 5 minutes.  We probably waited for 13 min and 42 sec but whos counting?  Anyway we then set up a ringstand with a paper funnel in the hole of the ringstand( must be folded triangularly bro and weighed).  underneath the filter paper was a clean beaker.  We then poured our 13 min and 42 sec combined solution into the filter paper and waited....and waited...for like 18min and 21 sec.  Then we found out we had a murky white substance in the beaker and some left over residue in the paper funnel.  We then saved our filter paper to weigh next time.  From our experiment we can conclude we had an excess and limiting reactant!!

yea i had to do this

 Na2CO3 + CaCl2 ---> CaCO3 + 2NaCl
this is the reaction and when we weigh the precipitate left behind in the filter paper we can determine which reactant is excess and which is limiting and by how much! omg so exciting






This is how you fold the filter paper

Sunday, March 13, 2011

Limiting and Excess Reactants

OK party people let MC JayLiu drop these beats on excess and limiting reactants

NO, that was NOT lame. In fact it's what all the fly kids by saying these days. Word

OKAY. So we see two terms from the title alone. Excess and limiting reactants? Let me put it in a way that most people can relate to.

Let's say for some unknown reason you want to make me a sandwich. Ingredients and supply? BREAD 10 pieces. SALAMI 489 slices. My sandwich consists of two pieces of bread with 267 slices of salami in between, no more, no less.

When we take a look at our bread supply, we see that we have to make five sandwiches. GREAT! Let's make 5 sandwiches.

HALT, EVIL DOER!

LOOK AGAIN, and you will see that we have a mere 489 slices of salami, enough to make 1 sandwich.

Therefore: only 1 sandwich can be made due to a LIMITING supply of salami, even though we have EXCESS bread. Also, JayLiu's 4th law of stoichiometry: One can never have EXCESS salami.

like this, without all that green crap


NOW, let's move away from the art of sandwich craft and move to ACTUAL Stoichiometry.

Eg. Butane burns in the presence of oxygen to form carbon dioxide and water. If 12.0g of butane reacted with 46.0g of oxygen, which reactant is excess/limiting and how many grams of CO2 will be produced?

STEP 1: WRITE THE EQUATION AND BALANCE

2 C4H10 + 13 O2 ------> 8 CO2 + 10 H2O

STEP 2: CONVERT ONE MASS INTO THE OTHER

(12.0g C4H10)(1 mol C4H10/58g C4H10)(13 mol O2/2 mol C4H10)(32g O2/1 mol O2) = 43.0g O2

since 43.0g < 46.0g, C4H10 is the limiting reactant by 3g

STEP 3: USING LIMITING REACTANT, FIND PRODUCT

(12.0g C4H10)(1 mol C4H10/58g C4H10)(4 mol CO2/1 mol C4H10)(44g CO2/1 mol CO2) = 36.4g CO2

Not the first video that appears when searching the query: "limiting and excess reactants".... the second

Tuesday, March 8, 2011

Molarity and Stoichiometry

This is an add-on from the previous blog.
This add-on costs $19.99
If you purchase this add-on you will be one step closer in reaching your Stoichiometriness.

BUY NOW

Aight, since you bought this add-on you will learn about Molarity.

Lets start with some examples

Eg. How many grams of Calcium will be formed when 100mL of 0.500M CuSO4 is reacted with sufficient Ca?

FIRST Make the equation
1 CuSO4 + 1 Ca ----> 1 CaSO4 + 1 Cu
Second Check if it is balanced
Now convert mL to L and convert to moles
0.100 L x 0.500Mol CuSO4
                ---------------- = 0.05 moles CuSO4
                         1 L
Now convert moles of CuSO4 to moles of Ca

0.05 mol CuSO4 x 1 mol Ca
                              ----------             =   0.05 moles
                              1 mol CuSO4
Now convert moles of Ca to grams by multiplying by the molar mass of Ca

0.05 mol Ca x 40.1g Ca
                       ---------    =   2.005 grams (REMEMBER SIG FIGS) =  2 grams
                       1 mol Ca

Here is a video to help you



Another part of your add-onn is
GAS STOICHIOMETRY (STP)

Here is an example of a gas stoichiometry problem

Zinc Carbonate decomposes into CO2 and Zinc Oxide. How many grams of ZnCo3 are needed to produce 8.0L of CO2 measured at STP?

First make your equation and balance it
1 ZnCO3 ---> 1 CO2 + 1 ZnO

Then convert litres into moles of CO2 to moles of ZnCO3

8.0L x 1 mol C02           1 mol ZnCo3    
           -----------      x   -------------- =   0.35714 moles ZnCO3
           22.4L CO2          1 mol Co2
NOW convert moles of ZnCo3 to grams

0.35714 mol ZnCo3 x  125.4 g ZnCO3
                                    ----------------  =  44.785356g ZnCO3 Round to sig figs 45g ZnCO3
                                      1 mol ZnCO

If you are still having some problems, please visit this website for more info
http://www.chemtutor.com/xmol2.htm

Sunday, March 6, 2011

AN ADD ON TO THE SUPER FUN W/E HE WROTE....its down below

You see, the last blogger wrote some random stuff about molar ratio and finding moles of different elements....yay....thats such loser stuff. THIS IS THE REAL STUFF.  This is what seperates pros from well people like the last blogger.  Anyway this is an add on to his lesson, this goes further into what stoichiometry is all about....annoying the heck out of people.

Instead of just finding moles of this and that, this time we will convert something like 5 moles of oxygen to 10 grams of what the hell.  The first step is to write out a balanced equation and find the molar ratios.  Then you will convert the number of moles of one element to another element.  Then you would do the same conversions you did in the previous chapters such as multiplying by 6.022 to the power of 23 to find the number of atoms.

It seems confusing and yes it is but this example will explain everything!  If not go read another blog or read the last bloggers post and then read another blog.

                                                  1 PbCl2 + 1 Mg = 1 MgCl2 + 1 Pb

find out how many grams of lead is needed to react with 5 moles of Mg.  Using the mole ratio we look at the place we are going over the where we are.  So when we convert it, it turns to 5 moles Pb.  Now we turn Pb into grams.  We multiply it by its molar mass.  It should be 207.2 times 5 =  1036 grams. The answer is we need 1036  grams of lead is needed to react with 5 moles of Mg.

Now if we changed the question to how many atomes of Pb is needed to react with 48.6 grams of Mg.  Then we will have to change Mg to moles by dividing it by its molar mass and it will be 2.  Then doing the exact same use the molar ratio from Mg to Pb and you will get 2 moles of Pb.  Now instead of going to grams you are going to molecules.  You are going to multiply 2 moles of Pb by 6.022 to the power of 23.  Now that is your answer.

Some cool teacher person talking for a long time non stop about some chemistry thing.  Not sure what it has to do with anything but watch it anyway. She literally talks for the whole time, go grab some popcorn its gonna be a long day.




cool story teacher, very cool.  Gonna watch that again

Wednesday, March 2, 2011

OMG ANOTHER FUN AND EXCITING CLASS!!!!

Today we learned about the proness of  MOLE + WORD EQUTIONS OMG OMG OMG OMG. How hax is it? I have no idea but we all know because it is chemistry it have to be FUN! Right? Yep that’s my into for today and maybe next time when I am more creative I’ll write more or other stuff but today isn’t my creative day. OKAY ON TOPIC So what did we learn today? We learned about this thing called st-----metry yea something like that... After looking through an immense amount of books many scholars finally decided on Stoichiometry. So what does Stoichiometry mean??? Honestly I have no idea, but according to Wikipedia it is about the quantitative analysis of chemicals reactions and measuring the amount of elements and compounds involved in a reaction. So basically it means measuring chemicals in numbers and the number of elements and compound in an reaction. What does Stoichiomety help us find out? It find how many molecules of whatever element that is in a reaction that the reaction started with. So is this thing useful? Not really but its life so we have to learn it. Going back  a bit Stoichiometry can be separated into 2 Greek words stoichio which menas elements and metry is measurement.
Let’s start with an example
I have 90000 Cl and 1 Na what will I get?
9000Cl+1Na à NaCl + 8999Cl
Even though I have over 9 thousand of Cl I can only produce 1 NaCl because Na is the limiting factor.
First Q
C3H8+5O2à 4H2O +3CO2 how many grams of H2O will be produced if I burned 215G of C3H8?
First make everything into moles
215g C3H8 * mol C3H8/44GC3H8 = 4.89 mol C3H8
4.89 molC3H8 * 4mol H2O/1mol C3H8 = 19.5mol H2O
19.5mol H2O* 18gH2O/1mol H2O = 352g H2O
There done
More questions
the number of moles of carbon dioxide formed when 40.0 mol of oxygen is consumed in the burning of propane.
C3H8 + 5O2 à 3CO2 + 4H2O
Molar Ratio 3 CO2 / 5 O2

40.0 mol O2 x 3 mol CO2 = 24.0 mol CO2
                          5 mol O2

A piece of iron (10moles) was dissolved in HCl. The reaction formed H2 and FeCl2 amount of FeCl2 formed and amound of HCl used.
  Fe + 2HCl = FeCl2+H2
10 mol Fe * 1mol FeCl2/1mol Fe  = 10mol FeCl2
HCl = 2(Fe) --> 20 moles of HCl was used.



Super typical chem teacher teaching on youtube.

Tuesday, February 22, 2011

Enthalpy Calculations

We begin with a story. Once upon a time there was a mole. One day, the mole disappeared. About 2 and a half months later, it returned. The end.

DELTA H ----> CHANGE IN ENERGY (kJ/mol)

But what does that mean? How do I find delta H?
CALM DOWN IM GETTING THERE.

Here's an example equation:

Ba + O2 --->  BaO + 1092kJ
Find delta H for 1 mole of product

STEP NUMERO UNO:
Look at it. Is it balanced? Is it equal? If I put both sides on either side of a scale would it even out? Yes, because they both weigh almost nothing? THAT IS BESIDE THE POINT. The point is, NO IT IS NOT BALANCED.

2Ba + O2 --->  2BaO + 1092kJ

Now, that looks much better.

STEP NUMERO DOS:

Take one part of the product side of the equation. In this case, only 2 BaO will do. Now take the energy (1092kJ) and put it into the form of kJ/mol like so:

-1092kJ/2 mol BaO

You may simplify this output to
-546kJ/1 mol BaO

So we just find delta H for these equations? NO
YOU CAN FIND ALL KINDS OF THINGS WHATEVER YOUR HEART DESIRES
except not, mostly just chemistry stuff

eg. Using the same equation (because im cool like that) Find the number of grams of O2 needed to produce 900 kJ of energy.

2Ba + O2 --->  2BaO + 1092kJ

Start with the energy needed to be produced:

-900 kJ

Find and utilize the conversion factor to end up with moles

(-900kJ)(1 mol O2/-1092) = 0.824 mol O2
Convert moles to grams:
(0.824 mol O2)(32g/1 mol O2) = 26.4 g

Asian guy explains everything

Saturday, February 19, 2011

Endothermic and Exothermic Reactions

Sooo first of all, all chemical reactions involve changes in energy. Some release energy to the surroundings (exothermic) and others absorb it (endothermic)

Eg. Nuclear bombs give off energy and are exothermic reactions.
Eg. Ice starts to melt which absorbs energy and are endothermic reactions.

We use something called an Energy Diagram to chart the Potential energy of the chemicals as they change from reactants to products.

Before we get into the diagrams, here are a few vocabulary words you should consider remembering:

Energy of Reactants  -  total potential energy of all recatants in the reaction
Energy of Products  -  total potential energy of all products in the reaction
Energy of the Activated Complex  -  Potential energy of the "transition state" between reaction and products
Activiation Energy  -  the change in Enthalpy in Potential Energy during the reaction.
Change in Enthalpy  -  the energy that must be added to get the reaction to progress
If you still do not the concept of the Potential Energy Diagrams; watch this video.








Monday, February 7, 2011

SUPER LAB AWAAAAAYYYY!!!!

TODAY WAS A SUPER EPIC LAB NO JOKES. What did we do? Well go read lab 5b in your workbooks noobs. Lazy? Fine. Well anyway we did 7 experiments. These experiments were to look at different types of chemical reactions(ex. synthesis, single replacement, etc. Anway the first experiment required us to...


EXPERIMENT 1

take 6cm of copper and hold in on the hottest part of the flame for a few minutes. The copper turned pink surprisingly and it took a while to notice any change

EXPERIMENT 2

Place a nail into a test tube and add copper sulfate so that half the nail is covered. This was a unique experiment. In the begining it seemed as if nothign happend but soon half of the nailed (the part covered by the copper sulfate) turned pink. After 15 minutes we removed the nail and we were surprised to see that the WHOLE NAIL turned pink with splotches of red. Really cool.

EXPERIMENT 3

Pute solid copper sulfate PENTAhydrate into a test tube and heat it for a long time over a bunsen burner. Just like a previous experiment with a hydrate, this leaves over a coloured white sand with white flake remnant instead of a blue powder

EXPERIMENT 4

We add water to our result from experiment 3. The result, unexpectedly, turns back to normal after rehydrating it after it evaporated all its h2o.

EXPERIMENT 5

fill test tube 1/4 full with calcium chloride. Fill 2nd tube with sodium carbonate. Then mix them together. I thought something totally awesome would happen, and well it turned to a milky white solution....COOL.

EXPERIMENT 6

cover mossy zinc with hydrochloric acid. This is quite interesting actually. When added the solution continually keeps bubbling and rises. It keeps on doing this for over 20 minutes which surprised me. This reaction can go on for a looooooooong time.

EXPERIMENT 7

Half fill the tube with hydrogen peroxide and add a small amount of manganese oxide as a catalyst. THEN YOU HAVE TO QUICKLY light a match and stick it. IT ACTUALLY IGNITES! TRUE DMG AND OVER TIME OMFG. LIKE BAM. LIT. A SPARK FROM THE GAS, TOTALLY AWESOME....NO ONE WAS BURNED THOUGH....we tried to imitate this twice but .....no it was a one timer....

EXPERIMENT 8!!!!!!!!!!!!!!!!!!

THE MOST EPIC EXPERIMENT EVAR

MIX EVERYTHING TOGETHER AND SEE WHAT HAPPENS

BEFORE: EMPTY TUBE AND MANY MANY MANY THINGS

DURING: MIX EVERYTHING TOGETHER AND IT STARTS TURNING DARK GREEN

AFTER: IT TURNS BLACK BUT SOME SAID IT WAS DARK GREEN NOT BLACK O WELL

This is the hydrate experiment we did without the calculations he did

Thursday, February 3, 2011

More Reaction Types

WHAT? MORE?!??! WHY OH WHY GOD HAVE YOU FORSAKEN ME!!?!?!

So yeah, looks like there are more of these to cover. None of which are new at all, so no need for the over dramatization.

Double Replacement

This is the Double Replacement reaction you know:
K2SO4 + BaCl2 ---> 2 KCl + BaSO4

Now here is that same reaction with the whole mess of crap that was added this year:

K2SO4(aq) + BaCl2(aq) ---> 2 KCl(aq) + BaSO4(s)

K(aq) + SO4(aq) + Ba(aq) + Cl(aq) ---> K(aq) + Cl(aq) + BaSO4(s)

Ba(aq) + SO4(aq)  ---> BaSO4(s)

As you may notice we have 3 separate equations. All of them however are essentially the same thing. The topmost is the balanced formula equation. (aq) determines that the item is aqueous while (s) determines that it is solid. To determine whether an item is aqueous or solid, use the table of solubility (all reactants are aqueous). The middle equation would be the Total Ionic Equation. To obtain this, separate all parts of the equation into individual elements or polyatomics, ignoring the coefficients. Items that are not aqueous cannot be separated. The last one is the net ionic equation which is obtained by cancelling items on either side of the total ionic equation like an algebraic equation.

Table of solubility


Combustion


This reaction consists of a chemical reacting with oxygen.

For hydrocarbons, the products will always include carbon dioxide and water
CH4(g) + 2 O2(g) ---> CO2(g) + 2 H2O(l)

For certain metals, the product will resemble a synthesis-like reaction
2 Fe(s) + O2(g) --> 2 FeO(g)

Neutralization


This reaction includes an acid + base as reactants and a salt + water as products. To form the salt take the chemicals that are not H or OH in the reactants and combine them in a synthesis like matter.

2 KOH(aq) + H2SO4(aq) ---> K2SO4(aq) + 2 H2O(l)


Thus conclude todays presentation. AND NOW FOR A VIDEO

Some nameless, faceless broad conducts a double replacement reaction in the name of SCIENCE. enjoy

Tuesday, February 1, 2011

Okay The MOST exciting lab we have EVER DONE

As the topic said This lab is SO FUN as most of us were astonished by the end of the class. The lab was sooooo fun. So you might be wondering what kind of lab did we do? IT IS A VIRTUAL LAB OMG. Instead of SEEING REAL RODS going BUBBLES we get to see some AWESOME Javascript animation that is totally easy to identify. Okay done with the random stuff. So what is this lab for? To learn more about single replacement and activity serious.
yea This is the real thing Cu(NO3)2
First we were presented 4 different kinds of solutions Mg(NO3)2, Zn(NO3)2,Cu(NO3)2, AgNO3 as we put the super cool animated rods into the solutions we got the results of Mg having the highest activity since it reacted with all of the solutions.

Then Cu rod was put in to the 4 solutions and only 1 rod changed there for it has less activity than Mg
After that Zn rod was inserted and 2 rod changed therefore Zn have higher activity than Cu but lower than Mg
and that leaves us with the last one Ag which didn't react with anything since it is the lowest of all in the Activity series. This is repeated with 4 other elements and it proves the activity serious.
Yep that is about all we did that class. and for the rest of the class most of us played around with the software and did our worksheet.
this is where we got our worksheet from in case you lost yours
http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/Metal%3DMetalIonTutorialtgrt.pdf
and this is where the software is...
http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/redox/home.html
yea this is just another exeriement done by someone else is about the same thing.


this is just cool. and it is single replacment double win

Friday, January 28, 2011

Types of Reactions

***Remember to balance!!!***

This stuff again? We covered that ages ago.
I KNOW WE DID!
BUT there is a little more to it this time.

First of all lets go over the 6 types of reactions.
Sythesis, Decomposition, Single Replacement, Double replacement, Combustion and Neutralization

Synthesis
This type of reaction combines 2 or more rectants to form a product

A + B ---> C

2Fe + 1O2 ----> 2FeO

Decomposition
This reaction breaks down a reactant into two or more products.

A ----> B + C

2FeO ---> 2Fe + 1O2

Singple Replacement
This reactions replaces the ion in an ionic compound.. Metal elements replace positive ions and Non-metal elements replace negative ions.

For Metals                                                      For Non-Metals
A + BC ----> B + AC                                       A+BC ---> C +BA

Ba + Ca(NO3)2 ---> Ca + Ba(NO3)2                     

Now for the extra thing I was talking about.
We are going to add something to spice up our equations.
Activity Series
The activity series is a chart which tells how reactive a metal or a a non-metal is.
The element higher up on the series replaces the ion below it on the table.
Here is what it looks like

*Note* There are more metals and non-metals that could be placed on this chart.


                                                                Reactive?
E.G. 2Li + MgCl2 ----> 2LiCl + Mg            YES

For more info please visit these following websites:


Wednesday, January 26, 2011

Balancing formulas and other stuff

AS USUAL I GET THE HARD BLOG AGAIN....anyways today we learned about balancing formulas

First of all before you go balancing and telling everyone your a pro at it, we should remember something we learned.  In the equation we have 2 sides.  We HAVE to make it equal or else its entirely bs.  Why you may ask? Because according to the law of conservation matter is never evar destroyed evar.

ok lets get to the learning...or review....mostly review.  Anyway  to balance the equation you must make sure that all the atoms on one side equals the number of atoms on the other side.  There is no cleverly developed way to do this.  The way to do this is by your preference.  I, however like to balance whole groups first (eg OH, SO4, CO2) then balance the atoms in their elemental form (eg O2, K, P4).  Then CHECK CHECK CHECK to make sure both sides are balanced or else you messed up and have to waste over 10 minutes to do it again HAH!  Ms.Chen said i didnt have to go into super tryhard details since this is review so this will have to do, to jog your memories kthxbai.


note how both sides equal to each other.  He added a 2 to H2 on the left side and added a 2 to H20 on the right side




Wednesday, January 12, 2011

Molar Volume of a Gas at STP

Sup, followers... or follower. Happy New Year and the like.

Pro Tip: When you read a word that is not actually a word and is in all CAPS it is usually an acronym.

SO WHAT COULD STP STAND FOR?


ALL WRONG


except for the last one, that one is correct

Standard Temperature and Pressure are measurements of temperature and pressure that are common in most experiments to allow easier comparison and contrast between different experiments. We want to keep these measurements the same because gases contract and expand as these measurements differentiate.

These measurements are  
Temperature: 0 °C (273.15 K, 32 °F)
Pressure: 1 At the Moment (atm)...............................................................atmosphere

Also: at STP, 1 mole of gas will have a volume of 22.4L

SO WITH ALL OF THAT SAID: MOLE CONVERSION TIME!!!!!!!!!

as with any mole conversion, we need conversion factors!

If 22.4L = 1 mole THEN:
22.4L/1mole OR 1mole/22.4L


Example Question:

Calculate how many moles of NH3 are in 5.6L of gas at STP

(5.6L of gas)(1 mole NH3/22.4L of gas)

L of gas cancel out

(5.6/22.4)moles of NH3

0.25 moles of NH3


dude with some what seems like a Beta version of MS paint teaches you about STP

Saturday, January 8, 2011

Diluting Solutions to Prepare Workable Solutions

Concentration is the amount of a substance that exists in a given volume of a solution. And we humans can lessen the concentration of a substance by diluting it. OMG wow so cool.

Wait, what is diluting you ask? This is the process of making a liquid thinner or weaker by adding water or another solvent into it.
Here is a picture of dilution                                            


As more solvent is added to each test tube, the solvent starts to get weaker or thinner.








You might say "We learned this already come on man/woman."

BUT WAIT IM NOT DONE YET MY PUPILS. This leads to the important part of this chapter.

The equation:  moles solute before = moles solute after.

WHATTTT???

In terms of molarity and volume: M1L1 = M2L2

*Note* Subscrite 1 means before and the subscript 2 means after

Here is an example :  Ex.  What volume of 8.00 M of HCl is used to make up 2.00L of 0.500 HCl

REMEMBER TO USE THE EQUATION

L1 = M2 x L2                     L1 = 0.500M x 2.00L
        -----------                  -----------------        =          0.125 L
             M2                               8.00 M

If you still do not understand,check out this website below.
http://www.ausetute.com.au/dilucalc.html

Thursday, January 6, 2011

It is happy new year with a touch of MOLARITY

hmm So what is Molarity???? To be honest I don't know :X. Jokes Molarity is the amount of solute dissolved in what ever volume of Solution 
okay? so What is Solute and Solution? HMMM as we were told this was once written into our brains a while ago and since our mind have always being written into since grade 1 most of the stuff that was ever written is erased so it makes perfect sense that no one remembers what solute and solution means. Okay enough random talking lets get to the real stuff so hmm what is solute and solution? Solute is the THING that is BEING DISSOLVED and Solution is THE THING THAT IS DISSOLVING THE SOLUTE (yes solution is all caps because it is cool that way unlike Johnny(FACT)) jokes

The Formula ahh math again...
 Nothing out of the normal 

Molarity = Moles of Solute(mole)/Volume of Solution (L)
M = mol/L  SEE WHY mole isn't M but the lame abbreviation of mol since Molarity decided to steal it..

okay the fun examples now 
4 grams (C12H22O11) is dissolved in a 350 ml teacup. What is the molarity of the sugar solution?
First step
C12H22O11= C(12)(12) + H(1)(22) + O(16)(11)
C12H22O11= 144 + 22+ 176
C12H22O11= 342 g/mol
4 g/(342 g/mol) = 0.0117 mol
350 ml x (1L/1000 ml) = 0.350 L
and the final step 
0.0117/0.35 = 0.033 mol/L
ahh that was lots of typing T T

Okay second question
How many moles of salt are contained
in 300 mL of a 0.40 M NaCl solution?
0.300 L x 0.40 moles NaCl
               1.00 L                 = 0.12 moles NaCl
Third question
15grams of salt with a molarity of 0.458M what is the volume of salt?
Atomic mass of NaCl is 58.5g/mole
15G x 1 mole/ 58.5g = 0.256410 moles
0.256410/0.458 = 0.56 Ml

okay a little game that i found using Molarity
  • Materials Needed:
    • computer
    • projector
    • molarity slides
    • periodic table
    • notes
    • wordbank
  • Procedure:
    • Opener:
      1. Review with students the formulas for molar mass (atomic mass = 1 mole), molecules (6.02 x 10^23 molecules = 1 mole), molarity (mole/liter), and toxicity (weight in kg * LD50).
    • Development:
      1. Divide class into 2 teams.
      2. Show the 5 categories. Explain that higher point questions are harder.
      3. Explain that each team must elect a captain, who will be the person to give the final answer.
      4. Explain that team 1 will choose a question to answer. Team 2 must also prepare to answer the question in case team 1 gives an incorrect answer. The team with the most points wins!
    • Closure:
      1. Suggestion: offer extra credit or free homework grade to the winners (although no incentive was necessary for a heated competition!).