We're the Grade 11s in Mr. Doktor's chemistry 11 class.
We're in Block A, Day 1.
We are
Theresa Nguyen
Dominika Skibicki
Charles Perea
Tim Pang
This is our blog.

ATOMIC MASS:
Atomic Mass= the mass of 1 mole of atoms in an element.

MOLECULAR MASS:
Molecular Mass= the mass of 1.0 mol of molecules of an element or compund.
(Eg.) If you have the element Magnesium, the symbol and formula is Mg. When you look at the atomic mass of the element it is 24.3 g/mol, making the molar mass the same. However if you have a diatomic compound like Iodine the symbol would be I and the formula would be I2. the atomic mass would be 126.9 g/mol but because the element is never by itself you have 2 of them. This means that you take the atomic mass and multiply it by 2, giving you a molar mass of 253.8 g/mol.

FINDING THE MOLAR MASS OF COMPOUNDS:
(Eg.) Iron(III)Sulphide: Fe2S3
The formula shows that there are: 2 Fe
3 S
and their atomic masses are: 55.8
32.1
you multiply the masses by the number of atoms: 55.8* 2=111.6
32.1* 3=96.3
now you add the 2 molar masses and get: 207.9 g/mol

CONVERTING MASSES <-> MOLES:
The conversion factors are g/mol or mol/g
(Eg.) find the mass of 2.5 mol of water...
H2o-> 18g/mol-> 2.5 mol* 18 g/1 mol= 45g

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