Steps
What is the first step to solve stoichiometry?
Balance the equation
2 H2 + 1 O2 ---> 2 H2O
How many moles of H2O is produced when we start with 5.00 moles of O2?
10 moles H2O
Fe3O4 + 4 CO--->3 Fe + 4 CO2
How many moles of CO are needed to react with 16.5g of Fe3O4?
.285 moles CO
2 H2 + 1 O2 ---> 2 H2O
How many grams of H2O will be produced from 15.0g of O2?
16.9 g H2O
What is the reagent that is not use up in a chemical reaction?
Excess reagent
What is the second step in solving stoichiometry problems?
Identify the given and unknown
1 KClO4 ---> 1 KCl + 2 O2
How many moles of KCl can be produced when 3.50 moles of KClO4 decomposes?
3.50 moles of KCl
Cl2 + 2Na ---> 2NaCl
How many grams of NaCl will be produced from 1.25 mol of chlorine gas reacting with sodium?
146 g NaCl
Cl2 + 2Na ---> 2NaCl
How many grams of NaCl will be produced when 75g of Na reacts with Cl2?
190.65 g NaCl
What is the reactant that is completely used up in a chemical reaction?
Limiting reagent
Where do the numbers for molar ratio come from?
THE BALANCED EQUATION
Fe3O4 + 4 CO--->3 Fe + 4 CO2
How many moles of Fe3O4 will form from 5.0 moles of Fe?
1.67 moles Fe3O4
2 H2 + 1 O2 ---> 2 H2O
How many moles of H2O will be produced from 26g of O2?
1.6 mole H2O
Fe3O4 + 4 CO--->3 Fe + 4 CO2
How many grams of CO are needed to react with 35g of Fe3O4?
16.9g CO
What are some reasons that a chemical reaction would seem to not follow the law of conservation of mass?
Human error (Wrong measurements, spilled chemicals
When we start in moles, what conversion method do we use?
Molar ratio/Molar bridge
1KClO4 ---> 1KCl + 2O2
How many moles of KClO4 must decompose in order to produce 9 moles of oxygen gas?
4.5 moles KClO4
1KClO4 ---> 1KCl + 2O2
How many grams of O2 will be produced from the decomposition of 4.50 moles of KClO4?
288g O2
1KClO4 ---> 1KCl + 2O2
How many grams of O2 will be produced from the decomposition of 46g of KClO4?
21g O2
Give me one example of a situation that follows the law of conservation of mass?
One example: camp fire
When we start in grams, why do we need to convert to moles?
We want to be able to bridge to a different substance.
2 C4H10 + 13 O2 ---> 8 CO2 + 10 H2O
How many mole of carbon dioxide is produced using 6.0 moles of C4H10?
24 moles CO2
2 C4H10 + 13 O2 ---> 8 CO2 + 10 H2
How many moles of CO2 are produced when 88g of O2 are reacted with excess of C4H10?
1.7 moles CO2
2 C4H10 + 13 O2 ---> 8 CO2 + 10 H2O
How many grams of C4H10 will be required to produce 56.0g of CO2?
18.5g C4H10
What is the mass relationship between substances in a chemical reaction?
Stoichiometry