Atomic Mass Unit (amu)= to the mass (wight) on the Periodic Table\

O = 16 amu

What is the amu of the following...

O= 16 amuH=1 amuC=12 amu

OH= 17 amuSiO₃= 76 amuSO₄=95 amu

HNO₃=63 amu

Monday, June 2, 14

Avagadorós Number (6.02x10²³)

1 mol = 6.02x10²³

ALWAYS

Molar Mass-The mass (aka weight) of ONE mole of

any substance

1mol = _____g 1 Element

Molar Mass = Atomic Mass in g/mol?Molar mass of O = 16g/mol

Monday, June 2, 14

Molar Mass of..

Mg=24.3 g/mol Cl=35.5 g/mol

MgCl₂=95.3 g/molAluminum Oxide=102

g/mol

Molar Mass of a compound:= the Sum of the Molar Masses of the

elements in that compound

How many Moles does 28g of N = 2 How many Moles does 24g of Mg = 1

Monday, June 2, 14

→

←

→

←

Grams of a Substance

Number of:1.Atoms

2. Molecules3.Formula

units

Mole of a Substance

÷ by molar mass

x by molar mass

x by Avagadrós Number

÷ by Avagardós Number

Monday, June 2, 14

Converting from Grams → MolesGrams←Moles

8.0g of Mg= ?Moles of Mg

molar mass =24.3g/mol

8g Mg x 1mol/24.3g Mg =.33 mol of Mg

?mol =34g of Cu(OH)2

Cu= 63.546O=15.999H=1.0079

34g x 1mol/97.5598 =.3485 mol Cu(OH)2

4.2mol Ca(NO₃)² = grams of Ca(NO₃)²4.2 mol x 164g/ 1 mol = 689 g of Ca(NO₃)²

Monday, June 2, 14

2Al + 3Cl₂→2AlCl₃

a. 2 Moles of Al will react with 3 moles of Cl₂ to produce 2 moles of AlCl₃.

b. How many moles of AlCl₃ will be produced if 7.5 moles of Cl₂ react?

7.5 mols Cl₂ x 2 mols AlCl₃ /3 mols Cl₂ = 5 Mol AlCl₃

Monday, June 2, 14

c. How many moles of Aluminum are needed to produce 3.6 mols of AlCl₃

3.6 mols of AlCl₃ x = 2mols of Al/ 2 mols of AlCl₃= 3.6 mols of Al

Monday, June 2, 14

Scientific Notaton: + -←Decimal→0.000104 1.04 x 10-⁴104,000,000 1.04 X 10⁸Multi:(3x10⁴)(2x10⁵)=

3x2=10⁴ + 10⁵ = 6 x 10⁹

(5x10³)(6x10³)= 30 x 10⁶(actually =s)3.0x10⁷In scientific notation your coefficient can not be more than 10

2x10⁷ ÷ 8 x10³ = .25 x 10⁴ →2.5nx 10 ³6x10⁶ ÷ 2x10³= 3 x 10³

Monday, June 2, 14

Moles→Molecules 4.99mol Methane = ?Molecules

4.99mols x 6.02 x 10²³ / 1mol = 30.04978 x 10²³ = 3.00x 10²⁴

3.5 x 10-⁵mol C₆H₈O₆ = ? molecules

3.5 x 10-⁵mol x 6.02 x 10²³ /1mol = 21.07 10¹⁸ = 2.1077 x 10¹⁹

Avagadorós Number (6.02x10²³)1mol = 6.022 x10 ²³ atoms

Monday, June 2, 14