STEPS
What is the first step you take when doing stoichiometry?
Write the balanced equation.
What do you need to find when you convert moles to moles?
Mole Ratio.
The branch of chemistry that deals with the calculation of the amounts of reactants and products involved in chemical reactions is called:
Stoichiometry
How many moles of Fe2O3 will form from 5.0 moles of Fe?
4Fe + 3O2 → 2Fe2O3
2.5 moles Fe2O3
What is the second step you take in stoichiometry?
Use the molar mass of your given substance to convert between grams and moles if required.
What do you need to find when you convert between moles and grams?
Molar Mass.
What conversion factor is indicated by coefficients in a balanced equation?
Mole Ratio.
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 third step you take in stoichiometry?
Use the mole ratio from the balanced equation to calculate the moles of your unknown substance.
When should you use Avogadro's number?
6.022x1023
When converting between moles and molecules or atoms.
Stoichiometry is based around ratios and the law of conservation of:
Mass
How many grams of NaCl will be produced from 1.25 mol of chlorine gas reacting with sodium?
2Na + Cl2 → 2NaCl
146.1 g NaCl
What is the last step in stoichiometry?
Convert from moles of your unknown substance to another unit (grams, molecules) if required.
Fe+O2--->Fe2O3
Find the mole ratio of Iron to Oxygen. Hint: you will need to balance your equation!
4:3
The reactant that is not used up when a reaction is run to completion is called:
Excess Reactant
Ammonium nitrate decomposes into dinitrogen monoxide and water. Determine the grams of water produced if 25.0 g of ammonium nitrate (NH4NO3) decomposes.
NH4NO3 → N2O + 2H2O
11.25 grams H2O