Mole
the SI base unit used to measure the amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly 12 g of carbon-12
Avogadro's Number
the number of particles in exactly one mole of a pure substance, 6.02 x 10^23
Molar Mass
the mass of one mole of a pure substance
Atomic Mass
Total mass of the protons and neutrons in an atom, measured in atomic mass units
Formula Mass
The sum of the atomic masses of all the atoms in a chemical formula
Stoichiometry
the study of the quantitive, or measurable, relationships that exist in chemical formulas and chemical reactions.
Mole-mole Problems
Conversion of moles of one substance into another.
Mass-mass Problems
1. BALANCE equation!
2. convert mass to moles
3. mole-relationship
4. convert moles back to grams (or liters)
Mass-volume Problems
a solution concentration expression that relates the mass of solute in grams dissolved in each 100g of solution
Volume-volume Problems
givens and unknowns in unit of liters (usually involves gases(mol at stp=22.4L) conversion factors are still based on mol to mol ratios
Limiting Reactant
the reactant that limits the amounts of the other reactants that can combine and the amount of product that can form in a chemical reaction
Expected Yield
The amount of product that should be produced based on stoichiometric calculations is the:
Actual Yield
the amount of product that actually forms when the reaction is carried out
Percent Yield
the ratio of the actual yield to the theoretical yield, multiplied by 100
Molar Volume
the volume occupied by 1 mole of a gas at standard temperature and pressure (STP); 22.4 L
Percentage Composition
the percentage by mass of each element in a compound
Empirical Formula
A chemical formula that shows the relative number of each type of atom in a molecule, using the smallest possible set of integers.
Molecular Formula
a chemical formula that shows the number and kinds of atoms in a molecule, but not the arrangement of the atoms
Balanced Chemical Equation
a chemical equation where both the reactants and the products contain the same amount of atoms for each element
Chemical Equation
an expression representing a chemical reaction; the formulas of the reactants (on the left) are connected by an arrow with the formulas for the products (on the right)
Coefficient
a small whole number that appears in front of a formula in a chemical equation