chemistry week 3

Definitions

Oxyacid (very strong acids)

Anions contains a non-metals and oxygen.

The hydrogen atoms can be released in solutions.

Definition - A compound that contains hydrogen atoms and anions.

Polyatomic Ion

combining a non-metal with an oxyanion; you get a polyatomic ion (post-fix) <-- -ate ; -ite

O2-4 and O2-3

Bronsted/Lowry Acids or Base

An acid is a substance (compound) that releases a hydrogen atom in solution.

• (proton donor base is a proton acceptor.)

mole calculations - definitions

a- based on exact numerical conversion factor related to mole calculations.

• Avagadro's Number - 6.022x10 23 things = 1 mole

• Gram molar mass - 1 mole = g weight (a.m.u)

mole calculations - Steps

step 1 - determine how many sig figs in the answer

step 2 - identify the unit being asked (desired) and identify the unit to be cancelled (undesired)

step 3 - determine the best numerical conversion factor to use.

step 4 - do the conversion

Stoichiometry Definition

Stoichiometry is a procedure used to "quantify" products made during a chemical reaction. (when you see grams use molar mass)

• understand the usefulness of conversion ratios in a chemical reaction/

• based on the law of conservation of mass

  • this is why all chemical equations must be balanced with the correct molar co-efficents.

Stoichiometry - Steps

step 1 - is the equation balanced

step 2 - determine how many sig figs

step 3 - identify which reactant/product conversion ratio to use.

step 4- determine the undesired unit and use that fact to get to the determined unit.