Can someone check my work (Hvap/Hcond Calculation)

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SUMMARY

The discussion focuses on the calculation of heat transfer during cooling and condensation, specifically using the equations q = m*deltaT*C and q = mols*Hvap. The user calculated the heat from cooling to be 721.05 joules (0.72105 KJ) and the heat from vaporization as 48.221 KJ. The total heat calculated is 48.221 KJ, with a clarification needed on the mass conversion from moles to grams, specifically for methanol, which has a molar mass of 32 g/mol.

PREREQUISITES
  • Understanding of thermodynamics principles, specifically heat transfer.
  • Familiarity with the equations for heat calculation: q = m*deltaT*C and q = mols*Hvap.
  • Knowledge of molar mass calculations and conversions between moles and grams.
  • Basic proficiency in using a scientific calculator for computations.
NEXT STEPS
  • Research the specific heat capacity of methanol to verify the calculation of heat transfer.
  • Learn about the concept of enthalpy of vaporization (Hvap) and its significance in thermodynamic processes.
  • Study the process of converting moles to grams using molar mass for various substances.
  • Explore common mistakes in heat transfer calculations to avoid errors in future problems.
USEFUL FOR

Chemistry students, educators, and anyone involved in thermodynamics or heat transfer calculations will benefit from this discussion.

Lori

Homework Statement


I don't have an answer key to these questions and it's my first time dealing with problems like this. so was wondering if my process is correct!
upload_2017-12-12_23-51-13.png

Homework Equations


q = m*deltaT*C
q = mols*Hvap

The Attempt at a Solution


So, my reasoning behind this work is that there was heat released from cooling and also heat from condensation. So, i found heat from cooling from the equation q = mdeltaTC = 2.53 J/gC * 30g * 9.5 = 721.05 joules = 0.72105 KJ. The heat heat from vaporization is just mols*Hvap = 48.221 KJ

Added together = 48.221 KJ. Was wondering if this is correct?
 

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Logic behind looks OK, but why 30 g?
 
Borek said:
Logic behind looks OK, but why 30 g?
i converted the 1.25 mol to mass with MM. is this correct?
 
And what is molar mass of methanol?
 
Borek said:
And what is molar mass of methanol?
Gotcha. Plugged it into calculator. Should be 40 grams
 

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