More on Moles...

Well... I'm going to start off with a funny story... My friend VIVIAN CHENG thought the "moles" were the black dots that grow on your face... then she thought it was the ANIMAL mole..... until i explained to her...

Well...we're still learning about moles, and how to convert moles... as much as I dislike moles, we still gotta learn about MOLES!...
Keep in mind Avogadro's Number  is 6.022 x 10^23 --> particles/mole

Molar Mass

You can convert molar masses from either:

1. Particles to moles
or
2. Moles to particles

Converting molar masses is somewhat simple. It is just like doing unit conversions.

For example:
1) Convert 4.5 x 10^24 particles to moles
4.5 x 10^24 particles x 1 moles/6.022 x 10^23 particles = 7.5 moles




What I did, was I divided 4.5 x 10^24 by 6.022 x 10^23. The particles cancel out. And because there is only one mole, the answer is simply 7.5 moles.

*Remember that you have to count to the correct number of significant digits.

2) *(2 atoms) Convert 0.82 moles CO₂ to molecules

0.82 moles x 6.022 x 10^23 particles/ 1 moles =   4.9 x 10^23 molecules CO₂

The moles cancel out, so you simply multiply 0.82 x (6.022 x 10^23) particles . Because its  4.9 x 10^23/ 1, it works out to just be 4.9 x 10^23 molecules CO₂

There are two atoms, so there is one more step involved. Well...it's not anything special... but...here goes!

4.9 x 10^23 molecules  CO₂  x 2 atoms O/ 1 molecule CO2  = 9.8 x 10^23 atoms of Oxygen 

And again... the molecules cancel out, and you just multiply the numbers. 

This video may help explain some questions you  may have: 

Are you tired of converting moles yet? Well we're almost done, so bear with me!
Now.. we are going to learn how to convert moles to grams, and grams to moles. Get your periodic table for this!!! We need it !!  To find the molar mass of an element, look for the atomic mass of the element!

Example:

1) Convert  3.06 moles Fluorine to grams
The molar mass of Fluorine is 19.0g/mol

3.06 moles x 19.0g/1 mole = 58.1 grams of F

Here, the moles cancel out, and you just multiply 3.06 x 58.1 grams of F...and.. BAM, you get the answer!


2) To convert 7.65 grams of Fluoride to moles
The molar mass of Fluorine is 19.0g/mol

7.65grams x 1 mole/ 19.0grams = 0.403 moles F

                                                                Remember this guys! 


Oh...my... I am Finally done :) ok... well now that my suffering is over... your turn to suffer!!!!
Here are some practice sites:
http://misterguch.brinkster.net/conversionsworksheets.html
http://www.sciencegeek.net/Chemistry/taters/Unit4GramMoleVolume.htm

This is another video to reinforce the idea of converting moles..




OK DONE! BYEBYE! =]