Atomic Mass, Formula Mass, and Molar Mass

Yay it was snowing last night :). Who doesnt love snow??? (besides people who drive.) Anyways, this blog is for science... So, the last 2 classes we learnt about different masses and how to find them. Here are the notes to remind you of what we know so far.

Avogadro's Hypothesis
- The volumes of different gases at the same temperature and pressure have the same amount of particles.
- If they have the same number of particles, mass ratio is caused by the mass of the particles
- This principle is used for the relative mass of all the atoms on the periodic table

Avogadro's Number (not phone number :p)
-The number of particles in 1 mole of any amount of substance is 6.022x10²³ particles/mole
- The mole allows chemists to count atoms and molecules a lot easier.
-Atoms can also be counted by weighing



Relative Mass
-It is the mass of the different elements that make up a particular formula.

Atomic Mass
- The mass of an atom of a chemical element expressed in atomic mass units. (Its found on the periodic table to make it easier.)

* amu stands for atomic mass units


Formula Mass
- All atoms of a formula of an ionic compound (in amu)
ex: Potassium has 39.1 atomic mass and Fluorine has 19.0. That would mean KF (potassium fluoride) would equal to 58.1 amu. Just need to add the atomic mass.

Molecular Mass
- All atoms of a formular in a covalent compound. (in amu)
ex: O2 would be 16.0u + 16.0u = 32.0u



Molar Mass
- The mass of 1 mole (6.022x10²³ particles) in a substance and is the same numerical value of atomic mass, formula mass, or molecular mass but expressed in GRAMS PER MOLE.
ex: The molecular mass of oxygen is 16.0u and the molar mass of oxygen is 16.0g/mole.



That's all for today :)
HAVE FUN IN THE SNOW!!