Methanol CH3OH Specific Heat Capacity Cp CV Isobaric Isochoric

Reference data and engineering information about methanol ch3oh specific heat capacity cp cv isobaric isochoric for thermodynamics applications.

methanolCH3OHspecificheatCalculatorData Table

Overview

Engineering reference data for Methanol CH3OH Specific Heat Capacity Cp CV Isobaric Isochoric in thermodynamics.

Key Formulas

First Law

$\Delta U = Q - W$

Energy is conserved — heat added minus work done.

Ideal Gas Law

$PV = nRT$

Relates pressure, volume, and temperature of an ideal gas.

Heat Transfer

$Q = mc\Delta T$

Sensible heat transfer.

Carnot Efficiency

$\eta = 1 - T_C/T_H$

Maximum efficiency between two temperatures.

Variables

Symbol	Description	Unit
$U$	Internal energy	J
$Q$	Heat	J
$W$	Work	J
$P$	Pressure	Pa
$V$	Volume	m³
$T$	Temperature	K

Data Tables

Isobaric Specific Heat (Cp) at Liquid-Gas Equilibrium

Isochoric Specific Heat (Cv) at Liquid-Gas Equilibrium

Unit Conversions

The following conversions apply to specific heat capacity units:

From	To	Factor
1 Btu/(lb·°F)	J/(kg·K)	4186.8
1 Btu/(lb·°F)	kJ/(kg·K)	4.1868
1 kcal(IT)/(kg·°C)	J/(kg·K)	4186.8
1 kcal(IT)/(lb·°F)	J/(kg·K)	5127.9
1 kJ/(kg·K)	J/(kg·K)	1000
1 kWh/(kg·K)	J/(kg·K)	3600000
1 J/(kg·K)	kcal(IT)/(kg·°C)	2.3885×10⁻⁴
1 J/(kg·K)	Btu/(lb·°F)	2.3885×10⁻⁴

Important Properties and Notes

Critical Point:

Temperature: 240°C (464°F)
Pressure: 82.16 bar (1192 psia)

Boiling Point (at 1 atm):

64.7°C (148.5°F)

Key Engineering Considerations:

Pressure dependence: For practical purposes, the specific heat of liquid methanol is approximately constant with varying pressure up to the critical point. This simplifies calculations for most industrial applications operating below 240°C.
Temperature dependence: Both Cp and Cv increase with temperature. The ratio Cp/Cv remains relatively constant (~1.20) for liquid methanol at moderate temperatures but increases significantly near the critical point.
Phase requirement: To maintain methanol as a liquid above 64.7°C, the system must be pressurized. At atmospheric pressure, methanol exists as a gas above this temperature.
Sharp increase near critical point: At temperatures approaching 510°C (237°C above critical), the specific heat increases dramatically due to critical phenomena—Cp reaches 34.6 kJ/(kg·K), approximately 14 times the ambient value.

Interactive Charts

References

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