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Stoichiometry
Stoichiometry means using balanced equations to calculate quantities of chemicals used in a chemical reaction
A chemical equation is like a recipe; it shows you how
much of each “ingredient” is used and how much product
you will have in the end.
N2 + 3H2 2NH3
How many molecules of N2 are there? 1
How many molecules of H2 are there? 3
How many molecules of NH3 are there?
N2 + 3H2 2NH3
How many molecules of N2 are there? 1
How many molecules of H2 are there? 3
How many molecules of NH3 are there? 2
N2 + 3H2 2NH3
You could also say that one mole of N2 will react with 3 moles of H2 to form 2 moles of NH3.
The heart of stoichiometry is using a
balanced chemical equation as a
conversion factor for dimensional analysis.
Zn + HCl ZnCl2 + H2
For the above reaction, how many moles of zinc chloride can be produced with 0.27 moles of zinc?
Zn + HCl ZnCl2 + H2
For the above reaction, how many moles of zinc chloride can be produced with 0.27 moles of zinc?
Balance the equation first!!!
Zn + 2 HCl ZnCl2 + H2
For the above reaction, how many moles of zinc chloride can be produced with 0.27 moles of zinc?
Balance the equation first!!!
Zn + 2 HCl ZnCl2 + H2
For the above reaction, how many moles of zinc chloride can be produced with 0.27 moles of zinc?
0.27 moles Zn x 1 mole ZnCl2 = 0.27 moles ZnCl2
1 mole Zn
Zn + 2 HCl ZnCl2 + H2
For the above reaction, how many moles of zinc will react with 1.39 moles of hydrochloric acid?
Zn + 2 HCl ZnCl2 + H2
For the above reaction, how many moles of zinc will react with 1.39 moles of hydrochloric acid?
1.39 moles HCl x 1 mole Zn = 0.695 moles Zn
2 moles HCl
Na + H2O NaOH + H2
Using the above equation, if we started with 0.15 moles of sodium metal, how many moles of hydrogen gas was produced?
2 Na + 2 H2O 2 NaOH + H2
Using the above equation, if we started with 0.15 moles of sodium metal, how many moles of hydrogen gas was produced?
0.15 moles Na x 1 mole H2 = 0.075 moles H2
2 moles Na