Wednesday
January 30, 2013
(Mole to Mass
Stoichiometry)
Hydrochloric acid reacts with magnesium hydroxide.
Predict the products and balance the equation.
15 moles of magnesium hydroxide will produce
how many moles of water?
15 mol Mg(OH)2
1
X
mol H2O
mol Mg(OH)2
=
30 mol H2O
4.78 moles of magnesium metal would
require how many moles of hydrochloric
acid to run the reaction between the two
substances to completion?
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Assignment
Currently Open
Summative
or
Formative?
Date
Issued
Date Due
Date Into
GradeSpeed
Final Day
QUIZ 16
S1
1/18
1/18
1/24
2/7
WS - Introduction
to Stoichiometry
and Mole Ratios
F7
1/23
2/1
2/1
WS – Review of
Molar Mass
F8
1/24
2/1
2/1
Project Share Quiz
– Reactions and
Balancing
F9
1/25
1/25
2/1
WS – Mole to
Mole
Stoichiometry
F10
1/29
2/1
2/1
Types of Stoichiometry Problems
Mole – Mass Conversions: Given is an
amount in moles and the unknown is a
mass in grams.
When you are given the amount in moles of one
substance and asked to calculate the mass of another
substance in the chemical reaction, the general plan
is:
Converting Moles to Mass
The following is a solution plan for problems in which
the given quantity is expressed in moles and the
unknown quantity is expressed in grams.
Converting Moles to Mass
Sample Problem
In photosynthesis, plants use energy from
the sun to produce glucose, C6H12O6, and
oxygen from the reaction of carbon dioxide
and water.
What mass, in grams, of glucose is
produced when 3.00 mol of water react
with carbon dioxide?
Converting Moles to Mass
Sample Problem
6 CO2 + 6H2O æ C6H12O6 + 6O2
3 mol
? grams
Sample Problem 9-3
Page 283
• What mass of carbon dioxide, in
grams, is needed to react with 3.00
mol of H2O in the photosynthetic
reaction described in Sample
Problem 9-2?
Mole – Mass Conversions
• Example: How many grams of glucose
are produced when 3.00 mol of water
react with carbon dioxide?
6CO2 + 6H2O → C6H12O6 + 6O2
Mole ratio of H2O to C6H12O6 : 6:1
3.00 mol H2O : 0.5 mol C6H12O6
Molar mass of C6H12O6 = 180.16 g/mol
0.5 mol of C6H12O6 = 90.08 g