Q3(b). Reading a one-component phase diagram
Answer the following questions based on the phase diagram given [P–T phase diagram with points A to H and 1 atm marked given in the paper]: (i) How many components does this phase diagram represent? (ii) Identify the points A to D with the corresponding degrees of freedom. (iii) Explain the changes expected along the paths E → B → H and E → F → G → H.
Answer in brief
One component; A normal melting point (F = 1), B normal boiling point (F = 1), C critical point (F = 0), D triple point (F = 0); vapour condenses sharply at B along E → B → H but becomes liquid without crossing a boundary along E → F → G → H.
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Coversphase diagramphase ruletriple pointcritical pointsupercritical fluidcontinuity of states
All parts of Question 3
- 3(a) Electronic and molecular geometry of BrF₅ and [ICl₂]⁻10 marks
- 3(b) Reading a one-component phase diagram20 marks
- 3(c) Thermodynamics of the H₂–O₂ fuel cell20 marks