Chemistry 05: Stoichiometry
Avogadro's number
6.02 x 10^23
What is a mole?
6.02 x 10^23 representative particles
Where can you find the molar mass of an element?
Periodic table
mole ratio
a conversion factor that relates the amounts in moles of any two substances involved in a chemical reaction
How do you find the molar mass of a compound?
add up the atomic masses of the component atoms
stoichiometry
analysis of the masses or amounts of substances involved in chemical reactions
particles
atoms and molecules
Where do mole ratios come from?
balanced chemical equations
How do you convert from particles to moles?
divide by Avogadro's number
How do you convert from mass to moles?
divide by the molar mass
If you want to convert between numbers of particles and mass, what must you first convert to?
moles
How do you convert from moles to particles?
multiply by Avogadro's number
How do you convert from moles to mass?
multiply by the molar mass
molecular mass
the mass in grams of one mole of a molecule
molar mass
the mass in grams of one mole of a substance
theoretical yield
the maximum amount of product that can be produced from a given amount of reactant
actual yield
the measured amount of product obtained in a chemical reaction
percentage yield
the ratio of the actual yield to the theoretical yield, multiplied by 100
excess reactant
the reactant that is not used up completely in a chemical reaction
limiting reactant
the reactant that limits the amount of the other reactant that can combine in a chemical reaction
How does the mass of the reactants compare to the mass of the products in a chemical reaction?
they are the same
Why do we balance chemical equations?
to preserve the Law of Conservation of Matter
Where are the reactants found in a chemical equation?
to the left of the arrow
Where are the products found in a chemical equation?
to the right of the arrow
Do chemical reactions have to be balanced to obtain mole ratios?
yes
What does the arrow mean in a chemical equation?
yields