Ammonia - Specific Heat vs. Temperature and Pressure

Specific heat (C) is the amount of heat required to change the temperature of a mass unit of a substance by one degree.

• Isobaric specific heat  (C_p) is used for ammonia in a constant pressure (ΔP = 0) system.
• Isochoric specific heat (C_v) is used for ammonia in a constant-volume, (= isovolumetric or isometric) closed system.

At ambient pressure and temperature the isobaric specific heat, C_P, of ammonia is 2.2 [kJ/kg K] or 0.52 [Btu/lb °F] = [cal/g K], while the isochoric specific heat, C_V, is 1.6 [kJ/kg K] or 0.39 [Btu/lb °F] = [cal/g K].

However,  the specific heat  - C_P and C_V - will vary with temperature. This may influence on the accuracy of ammonia conditioning and industrial ammonia handling process calculations. When calculating mass and volume flow of ammonia in heated or cooled systems with high accuracy - the specific heat should be corrected according values in the figures and table below, or found by use of the calculator.

• Heat capacity unit conversion

Online Gaseous Ammonia Specific Heat Calculator

The calculator below can be used to estimate the specific heat of gaseous ammonia at constant volum or constant pressure and at given temperature and pressure.
The output specific heat is given as kJ/(kmol*K), kJ/(kg*K), kWh/(kg*K), kcal/(kg*K), Btu(IT)/(mol*°R) and Btu(IT)/(lb_m*°R)

Temperature

Choose the actual unit of temperature: °C  °F  K  °R 

Choose the actual pressure:  1 bara / 14.5 psia; 10 bara / 145 psia; 50 bara / 725 psia; 100 bara / 1450 psia;

Load Calculator!

Load Calculator!

See also other properties of Ammonia at varying temperature and pressure: Density and specific weight, Dynamic and kinematic viscosity, Prandtl Number, Properties at Gas-Liquid Equilibrium pressure, Specific Heat (Heat Capacity) and Thermal Conductivity, and Thermophysical properties at standard conditions and Vapour pressure at gas-liquid equilibrium,
as well as Specific heat  of  Air - at Constant Pressure and Varying Temperature,  Air - at Constant Temperature and Varying Pressure, Butane, Carbon dioxide, Carbon monoxide, Ethane, Ethanol, Ethylene, Hydrogen, Methane, Methanol, Nitrogen, Oxygen, Propane and Water.

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Isobaric specific heat, C_P, of ammonia at given temperatures and pressures:

For full table with specific heat at Constant Pressure - rotate the screen!

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Isochoric specific heat, C_V, of ammonia at given temperatures and pressures:

For full table with specific heat at Constant Volume - rotate the screen!

• Solubility of Ammonia in Water

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Unit conversion:

Specific heat unit converter

british thermal unit(International table) = [Btu(IT)], degree celcius = [°C], degree fahrenheit = [°F], degree kelvin = [K], degree rankin = [°R], joule = [J], kilocalorie(International table) = [kcal(IT)], kilogram = [kg], kilojoule = [kJ], kilowatthour = [kWh], mole = [mol], pound =[lb]

K in the units can be replaced by °C, and vise versa. °R in the units can be replaced by °F, and vise versa.

• 1 Btu/(lb °F) = 1 Btu/(lb °R) = 1 kcal(IT)/(kg °C) = 1 kcal(IT)/(kg K) = 4186.8 J/(kg K) = 0.81647 kcal(IT)/(lb °F) = 1.163x10^-3 kWh/(kg K)
• 1 J/(kg K) = 1 J/(kg °C) = 2.3885x10^-4 kcal(IT)/(kg ^oC) = 2.3885x10^-4 Btu/(lb °F) = 1.9501x10^-4 kcal(IT)/(lb °F)
• 1 kcal(IT)/(kg °C) = 1 Btu/(lb °F) = 4186.8 J/(kg K) = 0.81647 kcal(IT)/(lb °F) = 1.163x10^-3 kWh/(kg K)
• 1 kcal(IT)/(lb °F) = 1.2248 Btu/(lb °F) = 1.2248 kcal(IT)/(kg °C) = 5127.9 J/(kg K)
• 1 kJ/(kg K) = 1 kJ/(kg °C) = 1000 J/(kg K) = 1000 J/(kg °C) = 0.23885 kcal(IT)/(kg °C) = 0.23885 Btu/(lb °F) = 0.19501 kcal(IT)/(lb °F) = 2.7778x10^-4 kWh/(kg K)
• 1 kWh/(kg K) = 0.85985 kcal(IT)/(kg °C) = 0.85985 Btu/(lb °F) = 3.6 kJ/(kg K) 
• 1 mol of air = 28.96546 g

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