2. Below is the phase diagram of sulphur. At 95.4°C, the densities of rhombic and monoclinic sulphur are 2.07 g cm³ and 1.96 g cm³, whilst the enthalpy change for phase transition from rhombic to monoclinic sulphur is 0.3 kJ mol1. Sulfur 153°C, 1420 atm Liquid 95.4°C 115.21°C 1 atm P Monoclinic 444.6°C 115.2°C, 3.2 x 10-5 atm Rhombic 95.3°C, Gas 5.1 x 10-6 atm i) How many triple points are there? ii) What is the most stable form of sulphur under normal conditions? iii) Describe what happens when sulphur at 1 atm is heated from 80°C to 200°C. iv) Determine the volume change AV for the transformation from rhombic to monoclinic sulphur. v) Estimate the pressure at which rhombic and monoclinic sulphur coexist in equilibrium at a temperature of 373 K.

2. Below is the phase diagram of sulphur. At 95.4°C, the densities of rhombic and monoclinic sulphur are 2.07 g cm³ and 1.96 g cm³, whilst the enthalpy change for phase transition from rhombic to monoclinic sulphur is 0.3 kJ mol1. Sulfur 153°C, 1420 atm Liquid 95.4°C 115.21°C 1 atm P Monoclinic 444.6°C 115.2°C, 3.2 x 10-5 atm Rhombic 95.3°C, Gas 5.1 x 10-6 atm i) How many triple points are there? ii) What is the most stable form of sulphur under normal conditions? iii) Describe what happens when sulphur at 1 atm is heated from 80°C to 200°C. iv) Determine the volume change AV for the transformation from rhombic to monoclinic sulphur. v) Estimate the pressure at which rhombic and monoclinic sulphur coexist in equilibrium at a temperature of 373 K.

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter7: Chemical Energy

Section: Chapter Questions

Problem 62E: In a coffee-cup calorimeter, 1.60 g NH4NO3 is mixed with 75.0 g water at an initial temperature of...

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