20.0 g of a solid substance X initially at 25.0 °C is heat to its melting point at 65.0 °C. Heat is continuously added until the substance completely melts. Which expression represents the total heat added (q) to X in units of kJ? Variables are defined below: J = specific heat of X in C MM (X) = molar mass of X in g mol AH fus = enthalpy of fusion of X in kJ AHvap = enthalpy of vaporization of X in kJ kJ q= (C) (20.0 g) (65.0°C 25.0°C) (100) + (20.0 g) (AHfus) J q= (C) (20.0 g) (65.0°C 25.0°C) 20.0 g q= (CX) (20.0 g) (65.0°C - 25.0°C) + (() (AHfus) kJ (1J) 1000 kJ 20.0 g q= = (CX) (20.0 g) (65.0°C - 25.0°C) (1000) + (MMX)) (AHfus) J 20.0 g q=(MMX) (AHvap) q= (CX) (20.0 g) (65.0°C kJ 25.0°C) (1000) + ( 20.0 g q= (CX) (2) (65.0°C - 25.0°C) g (100)+(2)(AHfus) MM kJ 20.0 g MM (X)) (AHvap) J

20.0 g of a solid substance X initially at 25.0 °C is heat to its melting point at 65.0 °C. Heat is continuously added until the substance completely melts. Which expression represents the total heat added (q) to X in units of kJ? Variables are defined below: J = specific heat of X in C MM (X) = molar mass of X in g mol AH fus = enthalpy of fusion of X in kJ AHvap = enthalpy of vaporization of X in kJ kJ q= (C) (20.0 g) (65.0°C 25.0°C) (100) + (20.0 g) (AHfus) J q= (C) (20.0 g) (65.0°C 25.0°C) 20.0 g q= (CX) (20.0 g) (65.0°C - 25.0°C) + (() (AHfus) kJ (1J) 1000 kJ 20.0 g q= = (CX) (20.0 g) (65.0°C - 25.0°C) (1000) + (MMX)) (AHfus) J 20.0 g q=(MMX) (AHvap) q= (CX) (20.0 g) (65.0°C kJ 25.0°C) (1000) + ( 20.0 g q= (CX) (2) (65.0°C - 25.0°C) g (100)+(2)(AHfus) MM kJ 20.0 g MM (X)) (AHvap) J

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

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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