1. Facts You Can’t Live Without

2. Facts You Can’t Live Without
All elements are represented by a capital letter, or a capital letter followed by a lower case letter.
If you have 2 capital letters in a row, there are 2 different elements.
Ex: NI N, I nitrogen, iodine
Ni nickel
CO C, O carbon, oxygen
Co cobalt

3. Facts You Can’t Live Without
Atoms: building blocks of matter, contain complete properties of element, neutral Molecules: 2 or more atoms joined together Ions: charged atoms Cation: positively charged ions Anion: negatively charged ions

4. Molecular Formulas Molecular Formula Atom 1 Atom 2 Atom 3 Atom 4 Type#
H2O H 2 O 1
-----
NaNO3 Na N 3
Mg(OH)2 Mg
PCl3 P Cl
NaHSO4 S 4
Mg3(PO4)2 8

5. Learning Check Molecular Formula Atom 1 Atom 2 Atom 3 Atom 4 Type #
H2O H 2 O 1
-----
NaNO3 Na N ? 3
Mg(OH)2 Mg
PCl3 P Cl
NaHSO4 S 4
Mg3(PO4)2 8

6. Learning Check
How many atoms total, and of each type, are in the following: C4H12 PbSO3 Al2(SO4)3 NI3

7. There are 2 molecules of NH3 formed
There are 2 molecules of NH3 formed. Each NH3 molecule contains 1 N atom and 3 H atoms. There are 2 total N atoms and 6 total H atoms on the products side of the equation.
This is a single molecule of N2, which contains 2 N atoms. There are 2 total N atoms on the reactants side of the equation.
There are three molecules of H2. Each H2 molecule contains 2 H atoms, so there are 6 H atoms total on the reactants side of the equation.
There are 2 molecules of NH3 formed. Each NH3 molecule contains 1 N atom and 3 H atoms. There are 2 total N atoms and 6 total H atoms on the products side of the equation.
There are three molecules of H2. Each H2 molecule contains 2 H atoms, so there are 6 H atoms total on the reactants side of the equation.