Determine the homolytic C-H bond strength in CH3OH employing the following data.

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SUMMARY

The discussion focuses on determining the homolytic C-H bond strength in methanol (CH3OH) using thermodynamic data and reaction kinetics. The standard enthalpy of formation (DfH) values provided include DfH (CH3OH) = -201.6 kJ mol-1, DfH (H2) = 218 kJ mol-1, and DfH (HBr) = -36 kJ mol-1. Reaction rate constants at two temperatures (300K and 350K) for the reactions involving CH3OH and Br2 are given, allowing for the calculation of the enthalpy change using the Arrhenius equation. The homolytic dissociation equation for CH3OH is CH3OH → CH2OH + H•.

PREREQUISITES
  • Understanding of thermodynamic concepts, particularly enthalpy of formation.
  • Familiarity with reaction kinetics and the Arrhenius equation.
  • Knowledge of homolytic bond dissociation processes.
  • Basic skills in chemical equation balancing and interpretation of subscripts.
NEXT STEPS
  • Study the Arrhenius equation and its application in calculating activation energy.
  • Research methods for calculating bond dissociation energies using thermodynamic data.
  • Explore the concept of homolytic vs. heterolytic bond cleavage.
  • Learn about the implications of temperature on reaction kinetics and rate constants.
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Chemistry students, researchers in physical chemistry, and professionals involved in reaction mechanism studies will benefit from this discussion.

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DfH (CH3OH) = -201.6 kJ mol-1
DfH (H) = 218 kJ mol-1
DfH (HBr) = -36 kJ mol-1
DfH (Br) = 111.9 kJ mol-1
CH3OH + Br  CH2OH + HBr k(300K) = 1 x 106 M-1s-1; k(350K) = 4 x 108 M-1s-1
CH2OH + HBr  CH3OH + Br k(300K) = 1 x 107 M-1s-1; k(350K) = 7.7 x 108 M-1s-1

Any help would be appreciated, I just can't figure out how to even start this problem. Thanks in advance
 
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Use the rate data to correlate with the temperature data and find the enthalpy of the reaction for the two equations.

Write the homolytic dissociation equation. Also clarify the subscripts.
 

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