Follow the actual Lab 01 screen from the initial setup through bubble and dew pressures, a TP flash, independent balance checks, and three pressure cases. Save the study as JSON, reopen it, restore a case, and calculate again.
19:06 recording14 chapters2 optional practice pausesEnglish male narration + captions
Open the guide and Lab, then follow along
Open the Week 1 Lab guide and Lab 01 in separate tabs. Have a calculator and paper ready.
Follow the ideal-model setup shown in the video. Check the temperature, pressure, overall composition and units before each calculation.
Leave Optional practice pauses on to predict the two new pressure cases and attempt the final pressure case. Select Continue to next chapter when ready.
Keep your calculations and saved JSON together so you can reproduce the results later.
This walkthrough demonstrates the Lab that you explored independently after Week 1. It adds a guided screen demonstration to that lesson.
The recording is 19:06. Two optional practice checkpoints add about 7 minutes; take longer whenever needed. You can turn the pauses off to watch first and repeat the steps afterward. No repeat exit-ticket or feedback submission is needed for this supplement.
English captions
Try it yourself
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Chapter 1 of 14Week 1 supplemental demonstration
Open Lab 01 and the demonstration guide
For small equations or controls, use Full screen and turn a phone sideways. Use the video controls to play, pause, change speed or set volume. On narrow screens, English captions appear below the image; in native video full screen, they appear inside the video. Chapter links deliberately jump to a new point. Optional practice pauses retain the current screen until you continue. In a downloaded MP4, pause manually when prompted.
The video could not be loaded. Use the download link, or follow the guide and transcript below.
Your action in this chapter
Guide page 1. Open Lab 01. Supplemental walkthrough: set up, predict, calculate, verify, save, reopen.
Transcript · Chapter 1
Welcome to this practical demonstration of Lab One. In our first classroom session, you began working with the lab independently. This video now shows the complete workflow, from choosing the system to saving your results and reopening them. Open the demonstration guide and keep page one beside the lab. Use the Lab One link on this video page. You can pause whenever you need to enter a value or write a calculation. The two activity stops give you time to make predictions and try a new pressure yourself. We will study one synthetic ideal binary mixture at a fixed temperature. Our main question is how pressure changes the liquid and vapor amounts. We will distinguish composition from amount, check both component balances, and preserve three cases in a comparison file. The lab contains controls for later topics. For this demonstration, stay with the ideal solution and the pressure comparison shown here. You do not need the additional model exercises to follow this first-week workflow.
Keep a calculation you can reproduce
Retain the ideal-model inputs, your total and component balance checks, and the comparison JSON. Reopening a JSON study restores the saved records. Restore a selected case and select Calculate to recompute the current results.
The Three-case example JSON is an optional reference containing the demonstrated cases. Save your own comparison JSON as you follow the steps; use the example if you want to inspect or reopen the demonstrated records.
In the final two chapters, attempt the 90 kPa case before opening the self-check. Record your prediction, calculation and any correction. This supplemental demonstration does not require another exit ticket or feedback submission.
Attempt each practice checkpoint before reading its check. The text matches the narration. You can download it or print this page after expanding the transcript.
Chapter 1: Open Lab 01 and the demonstration guide
Recording 0:00
Welcome to this practical demonstration of Lab One. In our first classroom session, you began working with the lab independently. This video now shows the complete workflow, from choosing the system to saving your results and reopening them. Open the demonstration guide and keep page one beside the lab. Use the Lab One link on this video page. You can pause whenever you need to enter a value or write a calculation. The two activity stops give you time to make predictions and try a new pressure yourself. We will study one synthetic ideal binary mixture at a fixed temperature. Our main question is how pressure changes the liquid and vapor amounts. We will distinguish composition from amount, check both component balances, and preserve three cases in a comparison file. The lab contains controls for later topics. For this demonstration, stay with the ideal solution and the pressure comparison shown here. You do not need the additional model exercises to follow this first-week workflow.
Your action: Guide page 1. Open Lab 01. Supplemental walkthrough: set up, predict, calculate, verify, save, reopen.
Chapter 2: Set up the synthetic ideal mixture
Recording 1:13
Under Chemical system, choose Teaching binary, synthetic. Under Liquid model, keep Ideal solution. The extra symbols in this option belong to notation used later in the course. We only need the ideal assumption today. Enter three hundred fifty kelvin for Temperature, ninety-five kilopascals for Flash pressure, and zero point five for Feed fraction, z one. Then select Calculate equilibrium. The numerical inputs are preferable to the sliders when reproducing an exact case. At this temperature, the selected property record defines saturation pressures of one hundred fifty kilopascals for component A and sixty kilopascals for component B. These are synthetic teaching values, not measurements of a real chemical mixture. They come from the chosen system, so there are no separate saturation-pressure boxes to fill in for this case. Keep temperature and feed composition unchanged throughout the pressure comparison. On our one-mole feed basis, the feed contains half a mole of each component. Record the system, ideal assumption, temperature, pressure, and feed composition on guide page one.
Your action: Guide page 1. Teaching binary · synthetic; Ideal solution; T = 350 K; P = 95 kPa; z₁ = 0.5. Synthetic Psat₁ = 150 kPa and Psat₂ = 60 kPa at this T.
Chapter 3: Predict before changing pressure
Recording 2:37
The lab may already display the ninety-five-kilopascal baseline when it opens. That is expected. Our predictions concern the two pressures we have not tried yet. Before changing the pressure, use guide page one to predict what happens at one hundred ten kilopascals and at eighty kilopascals. For each case, write whether you expect liquid only, vapor only, or both phases. Then predict whether the vapor fraction increases or decreases relative to the baseline. In the prediction control, consider the question about lowering pressure at fixed temperature and feed composition. Make your own choice before checking the results. Give a short physical explanation in the guide. Do not change temperature to produce your predicted outcome. Take about two minutes for these predictions. A brief sentence for each pressure is enough. An initial prediction can be wrong and still be useful if you later explain how the calculation changed your reasoning. Pause here and continue when both predictions are written.
Your action: Allow about 2 minutes. Write both predictions on guide page 1 before continuing.
Chapter 4: Read the bubble and dew boundaries
Recording 3:49
Select P, x, y, fixed temperature in the Diagram menu. The horizontal axis is composition of component one. The vertical axis is pressure. The solid bubble curve uses liquid composition, x one. The dashed dew curve uses vapor composition, y one. The diamond marks the overall feed at the selected pressure. Look at the two boundary results below the diagram. Bubble pressure uses liquid composition equal to the feed composition, zero point five. Half of one hundred fifty plus half of sixty gives one hundred five kilopascals. This is where the first vapor appears when pressure is lowered from the liquid side. Dew pressure instead specifies vapor composition equal to zero point five. Its reciprocal is half divided by one hundred fifty, plus half divided by sixty. Taking the reciprocal gives approximately eighty-five point seven one four kilopascals. These boundary calculations answer different questions. Their specified compositions are not the two endpoint compositions of the current ninety-five-kilopascal tie line. Record both boundaries on guide page one and use them to classify our pressure cases.
Turn to guide page two. Our flash pressure is ninety-five kilopascals, between the dew and bubble pressures. The phase label therefore reads Liquid plus vapor. Read the three large results separately. Liquid x one is about zero point three eight eight nine. Vapor y one is about zero point six one four zero. Vapor fraction, beta, is about zero point four nine three five. The first two numbers describe composition within each phase. Beta describes how much of the entire feed becomes vapor. Beta is a molar amount fraction, not the vapor composition and not a volume fraction. On a one-mole feed basis, about zero point four nine three five moles are vapor, and zero point five zero six five moles are liquid. The horizontal tie line connects the liquid and vapor compositions at the same pressure. The feed composition lies between them. Component A is more concentrated in the vapor than in the liquid. Record the baseline in the guide, keeping enough digits for the balance check that follows.
Your action: Guide page 2. P = 95 kPa: liquid + vapor; x₁ = 0.388888889; y₁ = 0.614035088; β = 0.493506494. On F = 1 mol: L = 0.506493506 mol and V = 0.493506494 mol.
Chapter 6: Check both component balances independently
Recording 6:35
Now check the answer independently on guide page two. Start with one mole of feed, containing zero point five moles of A and zero point five moles of B. For component A, multiply the liquid amount by x one, then add the vapor amount multiplied by y one. The liquid contains about zero point one nine six nine seven moles of A. The vapor contains about zero point three zero three zero three moles. Their sum is zero point five moles. For component B, use one minus x one and one minus y one. The liquid contribution is about zero point three zero nine five two moles. The vapor contribution is about zero point one nine zero four eight moles. These also sum to zero point five moles. The two phase amounts must sum to one mole, and each phase composition must sum to one. Small differences from these totals can arise if you calculate with rounded screen values. Keep additional digits during the calculation. The lab's small residual checks its equations, while your hand calculation checks that you understand the quantities being balanced.
Your action: Guide page 2. A: 0.196969697 + 0.303030303 = 0.5 mol. B: 0.309523810 + 0.190476190 = 0.5 mol. L + V = 1 mol. Retain precision before rounding.
Chapter 7: Connect the Rachford–Rice root to the amount
Recording 7:57
For a closer look at the amount calculation, choose Rachford, Rice, vapor fraction in the Diagram menu. You may revisit this chapter later if you first want to complete the practical workflow. For this ideal calculation, each K value is its saturation pressure divided by the flash pressure. Using kilopascals for both numerator and denominator gives dimensionless values. K one is one hundred fifty divided by ninety-five, approximately one point five seven eight nine five. K two is sixty divided by ninety-five, approximately zero point six three one five eight. The plotted function combines both component balances. At beta equal to zero it is approximately positive zero point one zero five three. At beta equal to one it is approximately negative zero point one zero eight three. The crossing between them is the physical root. That root is beta approximately zero point four nine three five, the same vapor fraction we just checked on a one-mole feed basis. The horizontal axis here is vapor fraction, unlike the composition axis of the pressure diagram. Return the Diagram menu to P, x, y, fixed temperature before saving the baseline.
Before changing anything, save the calculated baseline. Open Study workspace, reopen and compare cases. In Label for the next captured case, enter a clear name such as Baseline, ninety-five kilopascals. Return to the experiment export controls and select Export experiment. This downloads a study JSON file containing inputs, calculated results, property information, and any prediction or reflection. It also adds that exported study to the workspace comparison in this tab. The case label helps you recognize the result later. Check that the captured baseline has pressure ninety-five kilopascals in its inputs and the vapor fraction we just verified. Download current inputs only is a different button. It can preserve a setup, but it does not contain the calculated result. For this exercise, use Export experiment so your evidence includes the actual calculation. The comparison currently lives in browser memory. We will download the complete comparison after adding two more pressures. Keep the individual study download as well, and do not assume that the open tab alone is permanent storage.
Your action: Guide page 2. Study workspace → label Baseline 95 kPa → Export experiment. Confirm recorded result. Input-only download does not include calculated results.
Chapter 9: Raise the pressure to 110 kPa
Recording 10:52
Now test your first prediction. Change only Flash pressure to one hundred ten kilopascals and select Calculate equilibrium. Leave temperature at three hundred fifty kelvin, feed fraction at zero point five, and the liquid model ideal. The pressure is above the bubble boundary of one hundred five kilopascals. The result is Liquid only. Beta is zero, so all one mole of feed is liquid. Its composition is the feed composition, x one equal to zero point five. Vapor y one displays N A, with the explanation No vapor phase. This does not mean a vapor composition of zero. There is no bulk vapor phase whose composition we can report at this state. Compare this result with your prediction, then record it on guide page two. In the workspace, enter a new case label such as High pressure, one hundred ten kilopascals. Select Export experiment to capture this calculated case. We now have the two-phase baseline and one liquid-only case for comparison.
Your action: Guide page 2. Change only P to 110 kPa, then Calculate equilibrium. Liquid only: β = 0, x₁ = 0.5, y₁ = N/A. Label and Export experiment.
Chapter 10: Lower the pressure to 80 kPa
Recording 12:06
Test the second prediction by changing only Flash pressure to eighty kilopascals. Select Calculate equilibrium again. Eighty kilopascals is below the dew boundary of about eighty-five point seven one four kilopascals. The phase label now reads Vapor only. Beta is one, and vapor y one equals the overall feed composition, zero point five. All one mole of feed is vapor. Liquid x one displays N A because there is no bulk liquid phase. As in the previous case, this absent composition is not zero. There is no liquid component amount to calculate because the liquid amount itself is zero. Record the result and compare it with your prediction. At this fixed temperature, reducing pressure from one hundred ten through ninety-five to eighty kilopascals takes us from liquid to two phases to vapor. The vapor fraction remains zero or one while a state stays inside its single-phase region. Label this case Low pressure, eighty kilopascals, and use Export experiment. The workspace should now hold three distinct cases.
Your action: Guide page 2. Change only P to 80 kPa, then Calculate equilibrium. Vapor only: β = 1, x₁ = N/A, y₁ = 0.5. Label and Export experiment.
Chapter 11: Compare the three cases and export curve data
Recording 13:26
Open the workspace comparison and find the input pressure, phase, vapor fraction, and composition rows. Check that temperature, feed composition, and model remain the same across all three columns. Only the flash pressure changed. The comparison displays recorded fields from the exported studies. A missing phase composition may appear as Not recorded. In the underlying JSON, the absent phase composition is null. Neither Not recorded nor null should be replaced by zero. Also inspect the pressure units. The input pressure is stored in kilopascals, but the result pressure is stored in pascals. Ninety-five kilopascals and ninety-five thousand pascals represent the same pressure, not a disagreement. Use Curve CSV to download the selected diagram's data. For the pressure diagram, the pressure column is labeled P underscore P a, meaning pascals. This file is a sampled equilibrium curve, not the three-case comparison. Because temperature and the ideal system were unchanged, the pressure diagram itself is unchanged across our three cases. The current pressure marker and phase split move. Record a short explanation of that distinction on guide page two.
Your action: Guide page 2. Compare three recorded cases. inputs.P: kPa; result.P and CSV P_Pa: Pa. Absent compositions are N/A or null, never zero. Curve CSV exports the selected curve, not the case comparison.
Chapter 12: Download, reopen, restore, and recalculate
Recording 14:56
Turn to guide page three. In the workspace, select Download comparison and confirm that the JSON file is saved. Keep this file before clearing anything. For this demonstration, Clear comparison removes the three in-memory cases. It does not delete your downloaded files. Now use Load studies or a comparison JSON and select the comparison file you just downloaded. The three recorded cases return. Choose Restore beside the ninety-five-kilopascal baseline. This loads its saved controls. Check the system, ideal model, temperature, pressure, and feed composition, then explicitly select Calculate equilibrium. Restoring a file and producing a fresh result are separate steps. The comparison preserves recorded evidence, while Calculate equilibrium runs the current inputs again. Verify that the fresh result is Liquid plus vapor with beta about zero point four nine three five. Check the two phase compositions as well. Record in the guide that you reopened the file and reproduced the baseline. A saved file becomes useful evidence when another person, or your future self, can recover the settings and obtain the same result.
You are ready for an independent attempt. Stay on guide page three and keep the answer page closed for now. Use the same synthetic ideal mixture at three hundred fifty kelvin and feed composition zero point five. The new pressure is ninety kilopascals. Before running the lab, classify the phase using the two boundary pressures. Calculate liquid x one, vapor y one, and the vapor fraction by hand. Use the ideal bubble relation to find the liquid composition, the equilibrium relation to find the vapor composition, and the component balance to find beta. Then enter ninety kilopascals and select Calculate equilibrium. Compare your calculation with the result, and check both component balances on a one-mole feed basis. Label and export this new study if you want to retain it with your earlier cases. Allow about five minutes for your attempt. Write the substitutions and units, not just the final numbers. Continue to the final chapter and guide page four only after you have tried the calculation yourself.
Your action: Allow about 5 minutes. Attempt the 90 kPa calculation on guide page 3 before opening guide page 4 or the next chapter.
Chapter 14: Check the independent result
Recording 17:41
Now open guide page four and check your attempt. Ninety kilopascals lies between the dew and bubble pressures, so both liquid and vapor are present. From the ideal bubble relation, liquid x one equals ninety minus sixty, divided by one hundred fifty minus sixty. The result is one third. Vapor y one equals one hundred fifty times one third, divided by ninety, giving five ninths. The vapor fraction is the feed composition minus x one, divided by y one minus x one. This gives three quarters. On a one-mole feed basis, the liquid amount is one quarter of a mole and the vapor amount is three quarters. Component A contributes one twelfth of a mole in the liquid and five twelfths in the vapor, totaling half a mole. Component B contributes one sixth in the liquid and one third in the vapor, also totaling half a mole. If your answer differs, inspect the phase compositions and amount fraction separately. Retain your original attempt and correction. You have now completed the practical cycle: predict, calculate, check independently, save the evidence, and reopen it to reproduce the result.
Your action: Guide page 4, after attempting page 3. P = 90 kPa: x₁ = 1/3; y₁ = 5/9; β = 3/4; L = 1/4 mol; V = 3/4 mol. A balance: 1/12 + 5/12 = 1/2 mol. B balance: 1/6 + 1/3 = 1/2 mol.