Mole Madness
This number tells how many particles are in one mole.
6.022 × 10²³
This formula calculates percent composition.
(part ÷ whole) × 100
Before solving stoichiometry problems, you must do this to the equation.
Balance the chemical equation
Stoichiometry uses coefficients of a chemical equation to make this
mole ratio
This yield is the amount actually obtained in an experiment.
actual yield
0.172 mol of CH₄ contains this many molecules.
1.04 × 10²³ molecules
This concept explains what fraction of a compound’s mass comes from each element.
Percent Composition
In the reaction between AlCl₃ and NaOH, this reactant runs out first and determines product formation.
limiting reactant
The mole ratio between KBrO₃ and Br₂ in the reaction
KBrO₃ + 5KBr + 6HNO₃ → 6KNO₃ + 3Br₂ + 3H₂O
1:3
This yield is the maximum amount predicted from calculations.
theoretical yield
The mass of 1 mole of a substance is called this.
Molar mass
If lithium phosphate is 17.9% Li, an 81.1 g sample contains about this many grams of lithium.
14.5 g Li
This reactant remains after the reaction is complete.
excess reactant
To convert from grams of reactant to grams of product you must first convert grams to this unit.
Moles
This formula calculates percent yield.
(actual ÷ theoretical) × 100
Mass of 2.48 mol of NaNO₃
211 g
Sodium chloride is 39.3% sodium. A 92.4 g sample contains about this many grams of sodium.
36.3 g Na
Reactants of combustion reaction
hydrocarbon and oxygen gas
In stoichiometry, the step that uses mole ratios is called this type of conversion.
mole to mole conversion
If theoretical yield is 12.0 g and actual yield is 13.2 g, the percent yield is this.
110%
Molecules in 0.145 mol of CH₄
8.73 × 10²² molecules
If a compound is 40% element A, a 250 g sample contains this many grams of A.
100 g
products of combustion reaction
CO2 and H2O
The amount of product predicted by stoichiometry is called this.
theoretical yield
A percent yield greater than 100% usually means this happened in the experiment.
measurement error or impurities in the product