PChem312 s22 w1

...return to Chem 312 - home

Tuesday, Jan 11, 2022

- Lab 1:

View the following video titled NOVA: Absolute Zero, The Conquest of Cold (first 52 mins); transcript

Program Expectations to be recorded in your lab notebook/carbon copies will be collected for evaluation:

1) Document all historical people mentioned throughout the program (please use web or transcript linked above to correct all name spellings),

2) At ~4.50 min there is an experiment done with salt/ice/water...describe and briefly explain...

3) At ~8:45 min there is an experiment done by Boyle...describe and briefly explain...

4) What tool did Boyle need to make his research better? (hint: ~11 mins)

5) List the names of the 3 thermometer scales...2 are mentioned first (~12 mins) then the 3rd later...

6) Who proposed the erroneous "Caloric Theory"?

7) Who disproved the "Caloric Theory"?...and what did this persosn have in common with the person who proposed the theory?

8) What was Tudor's 1st "ice" ship called?

9) What was the name of the book written by Carnot?

10) What job did James Prescott Joule hold while developing his contribution to thermodynamics?

11) Who is attributed to inventing the frozen food industry?

12) Who is attributed to inventing "air cooling"?

Wednesday, Jan 12, 2022

Announcements

1) If you have not done so, please review the syllabus linked here.

2) Question: Is your computer up to speed? During this course, we will be using software such as Excel, WORD, Igor, etc. Although there are computers available on campus (specifically in CSB 373), it is most convenient for you to install this software on your computer (laptop preferred). It may be the case that a "ChromeBook" or other cloud-based OS device may have sufficed in the past, it will not work in PChem...but computers will be available in CSB 373. Please see/email me with any questions.

Class Assignments

1) I would like for you to watch the following video that discusses being proactive vs. reactive. I have found that PChem students who are most successful would describe themselves as being proactive. I think you will agree that we should all shoot for being proactive in our lives, but this is a clear skill that even I am working on improving. The video moves quickly, so I suggest you just listen the first time, then consider coming back to this view it again at another time. We will discuss this more in class when we meet in person.

Proactive vs. Reactive

2) If the above material is interesting, consider learning more about Stephen Covey or how to use the Franklin Planner.

Steven Covey - Wikipedia (optional)

Franklin Covey - Wikipedia (optional)

Franklin Planner - Wikipedia (optional)

Weekly Planner example page (optional)

...now on to PChem...

3) It is time to start reading the text. Please note, that reading any science textbook is NOT like reading other documents. The information is presented in a very dense way...this means that there is a lot of scientific language that needs to be read multiple times in order to make sense. There are parts of your textbook that when i read them, i ask myself what was the author thinking be including this...crap!

- Let's start by reviewing the MATH ESSENTIALS 1 section (Page 1-3). As you might already know, PChem uses the language of mathematics to organize its contents. Calc 1 and Calc 2 are prerequisites for this course (although they are sometimes waived). Yes we will be taking derivatives and later integrals, but more importantly, you need to be comfortable with math in general. Math is a tool and by the way, you cannot hate a tool, as in..."i just don't like hammers." Although you may have had a bad experience with math in the past, i will present math in a way that you will find it helpful...like how a hammer is really good at driving nails!

• Please review this section (pages 1-3) now. In your notes, please write down all of the units listed in Table ME1.2 and indicate whether you are comfortable with these units (check) or not (???).
• In Section ME1.2...sig figs...this is something you should know well!
• In section ME1.3...they suggest that writing out all of your work is strongly suggested since it allows you to go back and correct any errors. Please work this problem in your notes as if you were going to answer this question on an exam (ie. Show your work)...we can use Mathematica(R) and/or Excel(R) at a later time to solve such problems.

- Let's continue reading sections 1.1-1.3. You may not be able to read all of this in the 50 mins...i.e. now, so consider this homework. Remember when i said the author sometimes writes...crap...well the beginning of section 1.2 (page p7-8) is crap...but i understand why he added this section...math is a powerful tool. This is not a good example of how PChem will be presented. Much of the information is qualitative and we will begin our quantitative work on Friday.

END.

Friday, Jan 14, 2022

Announcements

1) Well it was not a full first week, but we have made it! Congrats.

2) I am making progress on cleaning/organizing the PChem lab and i look forward to seeing you on Tuesday to start glass blowing. As you noticed in the NOVA video, glass blowers who made thermometers where an integral part of quantifying temperature, which in turn allowed us to come to some fundamental principles about heat and the lack of heat, ie. cold. I will ask you to "sign up" to come in on Tuesday from 2-3, 3-4, 4-5, or 5-6. Since there are 15 in the class, we can meet in groups of 4. Stay tuned for more details.

3) The NOVA program never gets old. There was a statement made in the program stating..."I am foot soldier of science." As you think about the early days of the development of scientific principles there are certainly key historical players (now written down in your lab notebooks), but let's not forget all the others who work behind the scenes (the foot soldiers) making thermometers, preparing samples, etc, without them science would progress at a snails pace. Although it may be a bit too earlier for you to contemplate your role in science, but you too are a foot soldier. You represent a critical part of the scientific ecosystem. Some of you will go on to be the Antoine Lavoisier of your time, but most of us will continue to be foot soldiers for science and as you might expect, the scientific ecosystem needs lot of foot soldiers! Keep up the good work. If this topic resonates with you, consider having a look at this paper titled, The foot soldiers of science.

Class Assignment

1) Install Igor software on your computer...go to here and download version 8.0. Although you can use the software for a 30 day trial, I ask you to register/activate your copy using the info in this image/below (click on it to expand) ->

VAPG-PDSX-GZLA-XPKY-MJYU-YLUX-KNS <- cut and paste:

2) In a very general sense, "Thermodynamics is a branch of science that describes the behavior of matter..." (Sec 1.1, sentence 1). Let's start with the simple process of heating up (or changing the temperature of) water. From General Chemistry (this is review material not in your current text) you know that:

heat = (mass of H2O) * (specific heat of H2O) * (the change in temperature)

q (J)= mass (grams) * 4.184 (J/(g K)) * Δ (K)

- So, if you have 100 grams of water at 298 K and you want to heat it up to 308 K how much heat is required? (please write this out COMPLETELY in your notes) Answer: 4180 J <- note proper sig figs.

- What happens to the temperature of 100 grams of water (at 308 K) when 6920 J of heat added to it? (write it out, SHOW ALL WORK) Answer ...you tell me?

- If 8210 J of heat is added to an unspecified amount of water that increases in temperature from 298 K to 321 K, how much water was involved in this process? (yes...write it out, SHOW ALL WORK)

*STOP...just so that I am clear, I will check your notes once we are back in-person; these calculations will be evaluated as if they are a homework assignment. I expect that these calculation will show up in your notes in a synchronous way and not randomly worked out as if they are some type of worksheet.

...back to work...

Another behavior of matter that was discussed in Gen Chem was how substances under phase changes, like melting (s → l), freezing (l → s), evaporation (l → g), and condensation (g → l). When these phase changes occur, there is heat added, but there is no change in temperature since all the heat that goes into the substance makes or breaks the intermolecular forces/interactions and does not change the kinetic energy of the molecules. In reality, when we see a phase change occur, we often see changes in temperature, but it is important to note that you are seeing 2 separate processes occurring. If we consider ONLY phase changes we need to use the heat of fusion/vaporization, also known as the enthalpy of fusion/vaporization; ΔH_fus or ΔH_vap. As was the case above, units are critical. the units on ΔH is J or kJ per mole...kJ/mol.

- So, if you have 1.00 mole of solid H2O that undergoes a phase change to 1.00 mol of liquid H2O...how much heat is required? To answer this we need to know the ΔH_fus for water...which is 6.02 kJ/mol...(Show your work) Answer: 6.02 kJ

- If 32.1 grams of solid H2O undergoes a phase change to liquid H2O...how much heat is required? 'yes...you will have to convert grams to moles...(Show your work)

- If you have 2.68 moles of liquid H2O that undergoes a phase change to gaseous H2O...how much heat is required? To answer this we need to know the ΔH_vap for water...which is 40.7 kJ/mol...(Show your work) Answer: 109 kJ

- If 16.4 grams of liquid H2O undergoes a phase change to gaseous H2O...how much heat is required? (Show your work)

Note: since the ΔH_vap > ΔH_fus, this means that it take a lot more heat to boil water than it does to melt ice.

3) Please read Section 1.3. This section has a collection of bold terms...add these terms to your notes and if necessary, add a small definition. Please have this done by Monday.

Have a great weekend...be safe...be smart...relax.

END