Enthalpy of Water Calculator:
Enter the values of mass, m(g), specific heat capacity, C(J/g°C) and change in temperature, T(K) to determine the value of Enthalpy change, H(J).
Enthalpy of Water Formula:
Enthalpy is a thermodynamic property that reflects the total heat energy within a system. It includes both the internal energy and the energy required to displace the surrounding environment to make space for the system. For a substance like water, enthalpy is particularly important in processes like heating, cooling, phase transitions (like vaporization or melting), and chemical reactions. The enthalpy of water can be used to calculate the heat required or released during these processes.
Water, being one of the most common substances, exhibits specific heat capacity, a property that measures how much energy is needed to raise the temperature of a given mass by one degree Celsius. The enthalpy change of water can be used to assess the amount of heat gained or lost when it undergoes a temperature change, which is a vital aspect of thermodynamics in various applications, such as heating systems, industrial processes, and natural phenomena like weather patterns.
The formula for calculating the enthalpy change of water depends on its mass, specific heat capacity, and the change in temperature. The heat change (H) is directly proportional to the mass of the water, the specific heat capacity of water, and the change in temperature. The specific heat capacity of water is approximately 4.18 J/g°C.
Enthalpy change, H(J) in Joules is equal to the mass, m(g) in grams of the water multiplied by the specific heat capacity, C(J/g°C) in Joules per gram degree Celsius of the water, and then multiplied by the change in temperature, T(K) in Kelvin.
Enthalpy change, H(J) = m(g) * C(J/g°C) * T(K)
H(J) = enthalpy change in Joules, J.
m(g) = mass in grams, g.
C(J/g°C) = specific heat capacity in Joules per gram degree Celsius, J/g°C(4.18 J/g°C).
T(K) = temperature in Kelvin, K.
Enthalpy of Water Calculation:
- A 500 g sample of water is heated from 20°C to 100°C. Calculate the enthalpy change.
Given: m(g) = 500g, C(J/g°C) = 4.18 J/g°C, T(K) = 100 – 20 = 80°C.
Enthalpy change, H(J) = m(g) * C(J/g°C) * T(K)
H(J) = 500 * 4.18 * 80
H(J) = 167200J.
- A 200 g sample of water absorbs 8360 J of heat. Calculate the change in temperature.
Given: m(g) = 200g, C(J/g°C) = 4.18 J/g°C, H(J) = 8360J.
Enthalpy change, H(J) = m(g) * C(J/g°C) * T(K)
T(K) = H(J) / m(g) * C(J/g°C)
T(K) = 8360 / 200 * 4.18
T(K) = 10°C.