STEPS
What is the first step you take when doing stoichiometry?
Write the balanced equation.
In order to determine a limiting reactant, a conversion between these two must occur.
A reactant and product.
What is Stoichiometry?
Mass relationships between substances in a chemical reaction.
How do we convert moles to grams?
Multiply by molar mass.
Fe3O4 + 4 CO--->3 Fe + 4 CO2
How many moles of CO are needed to react with
16.5 g of Fe3O4?
0.285 moles CO
What is the second step you take in stoichiometry?
List your 'given' and 'unknown' information
What are you trying to find when you convert moles to grams?
Molar Mass.
What do we look at to find mole ratios?
The coefficients in a balanced equation.
Which side are the reactants on in a chemical equation?
Left side
4Fe + 3O2 --> 2Fe2O3
How many moles of Fe2O3 will form from 5.0 moles of Fe?
2.5 moles of Fe
What is the third step you take in stoichiometry?
Identify molar mass conversion factors
What is the molar mass of this molecule, Mg(NO3)2?
148.3 g/mol
What is a Theoretical Yield?
The maximum amount of a product that can be given off.
What is used to relate any two substances in a chemical reaction?
Mole ratio
2KClO3 --> 2KCl + 3O2
How many moles of KClO3 must decompose in order to produce 9 moles of oxygen gas?
6 moles KClO3
What determines the limiting reactant?
Which reactant produces the least amount of product.
What are you trying to find when you convert moles to moles?
The Mole Ratio.
What is Excess Reactant?
Reactant that is not used up when a reaction is run to completion.
Fe+O2--->Fe2O3
Find the mole ratio of Iron to Oxygen
4:3
Cl2 + 2Na --> 2NaCl
How many grams of NaCl will be produced from 1.25 mol of chlorine gas reacting with sodium?
146 g
For determining how much excess reactant is left over, what do you need to compare?
The amount of excess initially and the amount of excess reactant used in the reaction.
Where does the actual yield come from?
The experiment
What is used to tell the efficiency of the reaction?
Percent yield
2H2 + O2 --> 2H2O
How many moles of H2O would be produced from 4 moles of O2?
8 moles of H2O
NH4NO3 --> N2O + 2H2O
Ammonium nitrate decomposes into dinitrogen monoxide gas and water. Determine the amount in grams of water produced if 25.0 g of ammonium nitrate decomposes.
11.3grams H2O