Transcript Chapter 9 Stoichiometry part I Mole-mole problems Mass-mass problems Stoichiometry Calculations of quantities in chemical reactions This means using balanced equations to calculate quantities of chemicals used in.

Chapter 9 Stoichiometry
part I
Mole-mole problems
Mass-mass problems
Stoichiometry
Calculations of quantities in
chemical reactions
This 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 a 2NH3
How many molecules of N2 are there?
How many molecules of H2 are there?
How many molecules of NH3 are there?
So one molecule of N2 will react with 3
molecules of H2 to form 2 molecules of
NH3.
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 a ZnCl2 + H2
For the above reaction, how many moles
of zinc chloride can be produced with 0.27
moles of zinc?
For the above reaction, how many moles
of zinc will react with 1.39 moles of
hydrochloric acid?
As an experiment...
What is the ratio of the reaction of
adding sodium to water, producing
sodium hydroxide and hydrogen gas?
Na + H2O a NaOH + H2
So if we started with 0.15 moles
of sodium metal, how many
moles of hydrogen gas was
produced?
Why are mole/mole problems
impractical in a laboratory
setting?
If you have 2.7 grams of
sodium to begin with, how
many liters of hydrogen gas
can be produced?
Fe + O2 a Fe2O3
How many grams of iron (III) oxide can be
produced with 17.2g Fe?
How many grams of iron will react with
5.25 liters of O2 (@STP)?
How many molecules of O2 are needed to
produce 3.92g Fe2O3?