1. Phase Changes Elemental sulfur exhibits five (5) common phases. There are two solid phases of sulfur, known as S(I) (s) and S(II) (s), a liquid phase S (I), and two gas phases, one consisting of molecules of Sg (g) and one consisting of molecules of S2 (g). Here are the phases of sulfur at 1.0 atm pressure, with specific heats and the enthalpy of each phase transition: below 368 K ● 368-388 K ● 368 K transition 388 K transition 388-718 K 718 K transition 718-882 K 882 K transition above 882 K S(I) (s) S(I) (s) → S(II) (s) S(II) (s) S(II) (s) → S (1) S (1) S (1) 1/8 S8 (8) specific heat = 0.73 J/g-K AH = 0.401 kJ/mol specific heat = 0.78 J/g. K AH = 1.722 kJ/mol specific heat = 1.04 J/g.K AH = 45.08 kJ/mol specific heat = 0.73 J/g-K AH = 49.13 kJ/mol specific heat = 0.59 J/g.K S8 (g) ¹/8 S8 (8)→ ¹/2 S2 (8) S2 (g) a) Identify the normal melting point and normal boiling point of sulfur. b) Calculate the total quantity of heat required to heat 1.00 gram of sulfur from 25°C to 150.°C.

1. Phase Changes Elemental sulfur exhibits five (5) common phases. There are two solid phases of sulfur, known as S(I) (s) and S(II) (s), a liquid phase S (I), and two gas phases, one consisting of molecules of Sg (g) and one consisting of molecules of S2 (g). Here are the phases of sulfur at 1.0 atm pressure, with specific heats and the enthalpy of each phase transition: below 368 K ● 368-388 K ● 368 K transition 388 K transition 388-718 K 718 K transition 718-882 K 882 K transition above 882 K S(I) (s) S(I) (s) → S(II) (s) S(II) (s) S(II) (s) → S (1) S (1) S (1) 1/8 S8 (8) specific heat = 0.73 J/g-K AH = 0.401 kJ/mol specific heat = 0.78 J/g. K AH = 1.722 kJ/mol specific heat = 1.04 J/g.K AH = 45.08 kJ/mol specific heat = 0.73 J/g-K AH = 49.13 kJ/mol specific heat = 0.59 J/g.K S8 (g) ¹/8 S8 (8)→ ¹/2 S2 (8) S2 (g) a) Identify the normal melting point and normal boiling point of sulfur. b) Calculate the total quantity of heat required to heat 1.00 gram of sulfur from 25°C to 150.°C.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter17: Spontaneity, Entropy, And Free Energy

Section: Chapter Questions

Problem 128IP: Some nonelectrolyte solute (molar mass = 142 g/mol) was dissolved in 150. mL of a solvent (density =...

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