PChem312 s22 w1 - Revision history

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 :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 os foot soldiers! Keep up the good work. If this topic resonates with you, consider having a look at this paper titled, [[Media:FootSoldier.pdf|The foot soldiers of science.]]
+: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, [[Media:FootSoldier.pdf|The foot soldiers of science.]]
 ====Class Assignment====

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 ''...back to work...''
-:Another behavior of matter that was discussed in Gen Chem was how substances under '''phase changes''', like melting (s &rarr; l), freezing (l &rarr; s), evaporation (l &rarr; g), and condensation (g &rarr; 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 -> &Delta;H<sub>fus</sub> or &Delta;H<sub>vap</sub>. As was the case above, units are critical. the units on &Delta;H is J or kJ per mole...kJ/mol.
+:Another behavior of matter that was discussed in Gen Chem was how substances under '''phase changes''', like melting (s &rarr; l), freezing (l &rarr; s), evaporation (l &rarr; g), and condensation (g &rarr; 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; &Delta;H<sub>fus</sub> or &Delta;H<sub>vap</sub>. As was the case above, units are critical. the units on &Delta;H 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 &Delta;H<sub>fus</sub> for water...which is 6.02 kJ/mol...(Show your work) ''Answer: 6.02 kJ''

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 ''...back to work...''
-:Another behavior of matter that was discussed in Gen Chem was how substances under '''phase changes''', like melting (s &rarr; 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 -> &Delta;H<sub>fus</sub> or &Delta;H<sub>vap</sub>. As was the case above, units are critical. the units on &Delta;H is J or kJ per mole...kJ/mol.
+:Another behavior of matter that was discussed in Gen Chem was how substances under '''phase changes''', like melting (s &rarr; l), freezing (l &rarr; s), evaporation (l &rarr; g), and condensation (g &rarr; 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 -> &Delta;H<sub>fus</sub> or &Delta;H<sub>vap</sub>. As was the case above, units are critical. the units on &Delta;H 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 &Delta;H<sub>fus</sub> for water...which is 6.02 kJ/mol...(Show your work) ''Answer: 6.02 kJ''

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 ''...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 -> &Delta;H<sub>fus</sub> or &Delta;H<sub>vap</sub>. As was the case above, units are critical. the units on &Delta;H is J or kJ per mole...kJ/mol.
+:Another behavior of matter that was discussed in Gen Chem was how substances under '''phase changes''', like melting (s &rarr; 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 -> &Delta;H<sub>fus</sub> or &Delta;H<sub>vap</sub>. As was the case above, units are critical. the units on &Delta;H 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 &Delta;H<sub>fus</sub> for water...which is 6.02 kJ/mol...(Show your work) ''Answer: 6.02 kJ''

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 :VAPG-PDSX-GZLA-XPKY-MJYU-YLUX-KNS <- cut and paste:
 :::[[File:Igor_2022.jpg|thumb|300px|none]]
 :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:
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 :'''Note: since the &Delta;H<sub>vap</sub> > &Delta;H<sub>fus</sub>, 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.
 ''Have a great weekend...be safe...be smart...relax.''

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 :::- 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 also so up in your notes in a synchronous way and note randomly worked out as if they are some worksheet.'''
+'''*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...''

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 ::heat = (mass of H2O) * (specific heat of H2O) * (the change in temperature)
 ::q (J)= mass (grams) * 4.184 (J/(g K)) * &Delta; (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.''
 :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.
 ''Have a great weekend...be safe...be smart...relax.''
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