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Chem 106: Class/ Lab
Week 10
Sign in: Roster @ front of lab
Pick up returned papers
Put names on Molar Masses II if you did not have names on
form and resubmit
Pick up handouts (2)
For today’s experiment
Work with the lab partner(s) who set up fermentation with
you
Chem 106: Class/ Lab
Week 10
Turn in Today
1. Chemical Reactions
(Course/ Lab Manual pp. 49-51)
2. Reactions, Balancing, Stoichiometry Worksheet (Course/
Lab Manual pp. 65-67)
3. Stoichiometry / Limiting Reactant / Ideal Gas Law
(Completed Handout)
Have stamped before leaving lab:
Distillation (Course/ Lab Manual pg. 46)
Chem 106: Class/ Lab
Week 10: Week 11 is Spring Break
Due Week #12
1. Completed Fermentation Report form
(Course/ Lab Manual pg. 46)
2. Fermentation Post Lab Ques.
[Handout: Individually done]
Hydrochloric acid + sodium hydrogen carbonate
1 HCl(aq) + 1 NaHCO3 (s)
White = hydrogen
Red = oxygen
Gray = carbon
Green = chlorine
Purple = sodium
_ ___ + _ ___ + _ ___
Write a complete balanced
chemical equation for the
reaction by adding products and
stoichiometric coefficients from
the above reactants.
Hydrochloric acid + sodium hydrogen carbonate
1 HCl(aq) + 1 NaHCO3 (s)
White = hydrogen
Red = oxygen
Gray = carbon
Green = chlorine
Purple = sodium
1 CO2(g) + 1 H2O(l) + 1 NaCl(aq)
Write a complete balanced
chemical equation for the
reaction by adding products and
stoichiometric coefficients from
the above reactants.
Hydrochloric acid + sodium hydrogen carbonate
2 HCl(aq) + 2 NaHCO3 (s)
--
White = hydrogen
Red = oxygen
Gray = carbon
Green = chlorine
Purple = sodium
Draw a balanced molecular
representation for all of the products of
the reaction using the following key.
(One water molecule is shown.)

Carbon
Hydrogen 
Oxygen 
Chlorine
Sodium
✪
Hydrochloric acid + sodium hydrogen carbonate
1 HCl(aq) + 1 NaHCO3 (s)
In the previous case, all of the reactant
molecules react to produce products
and none remain. In this case some
reactant remains. Draw the molecule
that remains above.
White = hydrogen
Red = oxygen
Gray = carbon
Green = chlorine
Purple = sodium

Carbon
Hydrogen 
Oxygen 
Chlorine
Sodium
✪
Hydrochloric acid + sodium hydrogen carbonate
2 HCl(aq) + 2 NaHCO3 (s)
In the first case, all of the reactant
molecules react to produce products
and none remain. In this case some
reactant remains. Draw the molecule
that remains above.
White = hydrogen
Red = oxygen
Gray = carbon
Green = chlorine
Purple = sodium

Carbon
Hydrogen 
Oxygen 
Chlorine
Sodium
✪
Hydrochloric acid + sodium hydrogen carbonate
__ HCl(aq) + _ NaHCO3 (s)
_ ___ + _ ___ + _ ___
Follow the Demo and complete the Handout
http://chemconnections.org/general/chem106/106assign.html#CO2
HCl(aq) + NaHCO3 (s)
Trial 2: The same volume of unknown concentration of
HCl was added to each of the flasks using the same
amounts of NaHCO3 as used in Trial 1: 2 g, 4 g, 6 g
Examine the image above and select the correct statement below.
A)NaHCO3 is the limiting reagent in the yellow and blue.
B)HCl is definitely not the limiting reagent in all three cases.
C)Equal numbers of moles of HCl and NaHCO3 may have reacted
in green.
D)NaHCO3 is definitely the limiting reagent in all three cases.
HCl(aq) + NaHCO3 (s)
Trial 2: The same volume of unknown concentration of
HCl was added to each of the flasks using the same
amounts of NaHCO3 as used in Trial 1: 2 g, 4 g, 6 g
Examine the image above and select the correct statement below.
A)NaHCO3 is the limiting reagent in the yellow and blue.
B)HCl is definitely not the limiting reagent in all three cases.
C)Equal numbers of moles of HCl and NaHCO3 may have reacted
in green.
D)NaHCO3 is definitely the limiting reagent in all three cases.
Energy: Heat: Enthalpy (ΔH)
Distillation
http://chemconnections.org/general/movies/htmlswf/oil-refining.swf
Oil Refining:
http://science.howstuffworks.com/oil-refining4.htm
Energy Diagrams
Energy Diagrams
https://www.youtube.com/watch?v=rdCsbZf1_Ng
Kinetics: Rate & TIME
(What is a second?)
How fast is a reaction?
Calculations
Distillation (Course/ Lab Manual pg. 46)
Example
24.55 g
52.2 mL
0.990 g/mL
Example
24.55 g
52.2 mL
0.990 g/mL
4.5 %
Theoretical Yield Calculation
24.55 g
? g (theoretical)
4
Molar mass = 342.3 g/mol
? mol sucrose = 24.55 g / 342.3 g/mol
= 0.07172 mol
Molar mass = 46.07 g/mol
? mol C2H5OH = 4 x mol sucrose
= 0.2869 mol
? g (theoretical) = mol C2H5OH x 46.07 g/mol
= 13.22 g
__________________
? g (actual) = [4.5 % ,that is: 4.5/100] x 52.2 mL x 0.990
g/mL
= 2.33g
% Yield = g (actual) / g (theoretical) x 100
= 17.6 %
Chem 106: Class/ Lab
Week 10
Today’s experiment: Completion of
Chemical Reactions/ Fermentation/ Distillation
Due & stamped Today
Distillation (Course/ Lab Manual pg. 46)
Chem 106: Class/ Lab
Week #12 After Spring Break
1) Titration of Vinegar
Quantitative Acid-Base Reaction (Neutralization)
Using a standard NaOH aqueous solution
Determining the % Acetic Acid in vinegar samples
2) Exam 2
Refer to the Course Calendar
practice questions
2 pages handwritten notes, which are to be
turned in, plus Periodic Table allowed
Chem 106: Class/ Lab
Week #10
Pick up distillation kit from the stockroom. Assemble as
shown. Complete instructions in Lab Manual. Have
page 46 stamped before leaving lab.
Distillation (Course/ Lab Manual pg. 46)
Turn in Week #12 after Spring Break
Plus: Fermentation Post Lab on-line Ques. Handout
http://chemconnections.org/general/chem120/ethanol-ques-106.html
[Handout: Individually done]