STEPS
What is the first step you take when doing stoichiometry?
Write the balanced equation.
What are you trying to find when you convert moles to moles?
The Mole Ratio.
What is Stoichiometry?
Mass relationships between substances in a chemical reaction.
When is 22.4 used as the molar volume?
When the gas is at stp.
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
5 mol of He is how many grams?
5 mol x 4 g = 20 g
Where do we look to find mole ratios?
The coefficients in a balanced equation.
What is Avogadro's number?
6.022x10^24
Fe + O2 -> Fe2O3
How many moles of Fe2O3 will form from 5.0 moles of Fe?
2.5 moles
If your given is a mass (ex: 4g of NaCl) what would be your first conversion?
Convert from Mass to moles of the unknown substance. (Divide by molar mass)
50 g of Ca is how many moles?
Ca = 40 g/mol
50 g / 40 g/mol = 1.25 mol Ca
What is Actual Yield?
Actual amount of a product that can be formed during an experiment.
How do we convert moles to grams?
Multiply by molar mass.
KClO3 -> KCl + O2
How many moles of KClO3 must decompose in order to produce 9 moles of oxygen gas?
6 moles KClO3
How would you convert from moles of one substance to moles of another substance?
Use the mole ratio
10 moles of Cu(NO3)2 is how many grams?
BONUS: What is the name of the compound?
Molar Mass Cu(NO3)2 = 187.56 g/mol
187.56 g/mol x 10 mol = 1875.60 grams
COPPER (II) NITRATE
What is a Theoretical Yield?
The maximum amount of a product that can be given off based on calculations.
What are you converting from and to if you divide by 6.022x10^23 then multiply by molar mass?
Converting from particles to grams
How many grams of NaCl will be produced from 1.25 mol of chlorine gas reacting with sodium?
146 g
Describe the process to calculate the mass of bromine needed to produce 4g of CaBr2.
1. Write a Balanced Equation
2. Convert 4g CaCl2 to moles of CaBr2 using molar mass
3. Convert moles of CaCl2 to moles of Br using mole ratio
4. Convert moles of Br to Mass of Br using molar mass
Fe+O2--->Fe2O3
Find the mole ratio of Iron to Oxygen
4 Fe : 3 O2
What is Excess Reactant?
Reactant that is not used up when a reaction is run to completion.
What is a mole?
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.
11.3 grams H2O