OCTOBER 20

To start off class and continue our talk about moles Mr.doktor showed a clip from the Austin powers 3 movie.


Atomic Mass
-The mass of 1 mole of atoms of an element
The mass of 1 mole of "c" atom is 12.01g
The mass of 1 mole of "ca" atom is 40.1g

Molar mass
The mass if grams of 1 mole of molecules of an element or compound is the molar mass

Diatomic numbers
H2, O2, N2, Cl2, Br2, I2, F2

Polyatomic numbers
P4,S8

We did a chart to give us some practice how molar mass is calculated.
Element Symbol Formula Atomic mass Molar mass
Bromine Br Br2 79.9 159.8
Neon Ne Ne 20.2 20.2
Silicon Si Si 28.1 28.1
Hydrogen H H2 1 2
Iron Fe Fe 55.8 55.8

To find the molar mass it is basically like this
Equation - >Ca(NO3)2
1.find out how many elements their are in the equation
Ca=1
N=2
O=6
2.Look on the periodic table and get the atomic mass of the element and times it by how many elements their are in the equation then add
Ca=1x40.1 -> 40.1
N=2x14 - > 28
O=6x16 - > 96
40.1 + 28 + 96 = 164.1g/mol

We also learnt how to convert grams to moles and moles to grams.
Mr.Doktor also mentioned that for how air balloons it is filled with helium instead of hydrogen.If hydrogen is used instead the balloon will burst when coming close to fire.

HOMEWORK:

Unit 2 homework questions # 1-4