Qrtr 4 final

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The Mole
The coefficients in front of molecules represent moles.
This number is 6.02 x 10 23 . It's a big number. It is just a quantitative unit.
The mole (or mol) is Avagadro's number.
The amu of a molecule is the sum of all the amus of each element.
The mole of a molecule is basically the same as the amu.
So in terms of CO 2, a mole of Co2 would be 44.01 grams.
!1 mole of anything is the atomic mass in grams! (like how 12 grams of carbon-12 is 1 mole)
Molar mass: Grams per mole
In order to find the atoms of a particular element, you just have to do a conversion chart.
For example:
3.50 mol of H2O 6.02 x 10 23 molecules of
H2O
1 mol of H2O
3.50 x 6.02 x 10 23 = 2.11 x 10 24 molecules
of H2O
*To visualize the size of every atom, there are about 1 million carbon atoms in the width of
one hair.
4 moles of oxygen would be 64 grams (16 * 4)
Molar Ratios:
A Ratio of the amounts of reactants and products using the coefficients of a chemical
reaction.
2H 2 (g) + 1O 2 (g) ---> 2H 2 O 1 (these are coefficients)
Another example: 2H 2g + O 2g --> 2H 2 O 1
(that reduces to one)
The mole ratio from Hydrogen to water is 2 mole H2
2 moles of H 2 O
Moles to Grams: How many grams in 3.50 Moles of Water?
The molar mass of water is 18.02 g H 2 O
3.50 mol H2O x 18.02 g H2O
1 mol H2O
---> 3.50 x 18.02 + 63.1 g H2O
Grams to Moles: How many moles in 153.0 Grams of NaCl?
153.0 g NaCl x 1 mol NaCl =--> 153.0 g/ 58.44 = 2.618 mol NaCl
58.44 g NaCl