Matter

whats-the-matter

Particle Diagrams show phases.  This shows all 3 phases of matter.
Chemical Formulas show the number of each type of atom in a compound.  When there is NO number, that means just one.  Chemists hardly ever write the number 1.
In a chemical reaction new substances form with new chemical and physical properties.
You knew this before you met me. We'll spend a whole week learning about water later on.
The best element of them all.  All periodic tables are slightly different in the information that they show.  This shows that Hg, mercury is number 80, has 80 protons and electrons, and a total mass of 201 amu (we'll round).
In a chemical equation you start out with reactants that form into products.  There are always the same number of atoms of each kind on BOTH SIDES of the arrow.   This is called the LAW OF CONSERVATION OF MATTER, and it's important and can't be broken either.
Carbon is atom #6, with six protons and six electrons.   It's mass is 12 atomic mass units, which is abbreviated with the letter "u" as in 12 u.  (silly isn't it!)
In every chemical reaction there is a "conservation of matter" or mass.  That means the stuff you start with must still exist on the other side of the arrow, even though it's bonded together differently.  It's still ALL THERE.
There are 5 chemical reactions to start the year, then one more, then many more.  Start making index cards to study with, you need an example of each in your head.