Monday, Feb. 3rd: “A” DayTuesday, Feb. 4th: “B” Day

AgendaHomework Questions/ProblemsSec. 12.3 QuizLab Write-up: “Stoichiometry: Mass-Volume”Mini-lab: “How Much Gas is in a Bottle of Pop?”Homework: “Chemistry Gas Law Practice” WSChapter 12 Test/Concept Review Due:

“A” day: Tuesday, Feb. 11th

“B” day: Wednesday, Feb. 12th

Homework Questions Practice pg. 442: #1-3Sec. 12.3 review: pg. 442: #1-12

Additional Practice #2Methane has a volume of 0.65 L when under 100 kPa of pressure at a temperature of 305 K.

Using the balanced equation below, find the mass of oxygen that is needed to use up all of the methane.

CH4 + 2 O2 CO2 + 2 H2OUse PV = nRT to find moles of methane(100 kPa) (0.65 L) = n (8.314) (305 K)n = .026 mol methane Use stoichiometry and molar mass to find mass of

oxygen needed 1.66 g O2

Sec 12.3 Quiz“Molecular Composition of Gases”

You may use your book and your notes to complete the quiz on your own…

May the force be with you!

Lab: “Stoichiometry: Mass-Volume”Discussion

A common way of collecting gaseous products is by water displacement.

The reactants are placed in a closed reaction vessel with a gas delivery tube attached.

The delivery tube passes through a pneumatic trough filled with water and under an inverted gas collection vessel that is filled with water.

As the reaction proceeds, the gas leaves the reaction vessel and enters the collection vessel through the gas delivery tube, displacing the water.

Lab: “Stoichiometry: Mass-Volume”Discussion

The volume of gas produced is equal to the volume of water displaced in the gas collection vessel.

Since the gas is collected through water, the gas product is considered to be “wet” and this must be accounted for in calculations.

Conditions in our lab must also be converted to STP conditions to find the volume of dry gas produced at STP.

Lab:“Stoichiometry: Mass-Volume”

PurposeIn this lab, you will be producing, capturing, and

measuring the amount of CO2 gas produced by the decomposition of lead carbonate and comparing that to the theoretical yield using the following reaction:

Δ(PbCO3)2 Pb(OH)∙ 2 (s) 3 PbO(s) + 2 CO2 (g) + H20 (g)

Based on the purpose of the lab, come up with a hypothesis.

Lab:“Stoichiometry: Mass-Volume”

Hypothesis

Lab:“Stoichiometry: Mass-Volume”

Changes to Materials List

Add lead carbonate. (PbCO3)2 · Pb(OH)2

Cross out the size of the test tube (18 X 150 mm)Change thermometer to temperature probe.Cross out the barometer – I will get the

atmospheric pressure reading for that day online.

Lab“Stoichiometry: Mass-Volume”

Procedure Discussion

Prepare the data table as instructed before step #1 in procedure today. Include UNITS!

Lab: “Stoichiometry: Mass-Volume”Lab Write-up

Read through the rest of the lab and complete the write-up.

Don’t forget to leave room for your reflection statement.

Be sure to update your table of contents.

When you finish, pick up the “mini-lab” and read through the procedure…

Mini-Lab: “How Much Gas is in a Bottle of Pop?”

I thought this would be a fun lab as well as good practice for the upcoming stoichiometry lab.

You will use the same gas collecting procedure for this mini-lab as you will in the stoich lab.

Predict how much CO2 you think is in a bottle of pop.

Mini-Lab: “How Much Gas is in a Bottle of Pop?”

600 mL of hot tap water works well in the beaker.You can use a hot plate to gently heat the water

in the beaker to speed up the release of CO2.

Have Fun!