Definition of Specific Heat Capacity
Specific heat capacity refers to the amount of energy that must be added to a substance to raise its temperature by a certain degree. It is a property of materials and is defined as the amount of heat required per unit mass of a substance to increase its temperature by one degree Celsius. The specific heat capacity of a substance depends on its chemical composition and physical state.
Specific Heat Capacity Formula
The formula for specific heat capacity is given by:
`C = Q / (m ΔT)`*
Here, C is the specific heat capacity, Q is the amount of heat added, m is the mass of the substance, and ΔT is the change in temperature. The unit of specific heat capacity is joules per kilogram per degree Celsius (J/kg·°C).
Example of the Specific Heat Capacity Calculation
Suppose we want to find the specific heat capacity of 100 grams of water. We heat the water with an electric heater, and the temperature rises from 20°C to 60°C. The amount of heat added is given by Q = m c ΔT, where m = 0.1 kg, ΔT = 40°C, and c is the specific heat capacity of water. The specific heat capacity of water is 4,184 J/kg·°C.
Substituting the values, we get:
`c = Q / (m ΔT) = 20,000 J / (0.1 kg 40°C) = 500 J/kg·°C`
Thus, the specific heat capacity of water is 500 J/kg·°C.
Importance of Specific Heat Capacity Formula
The specific heat capacity formula is important in many fields, including chemistry, physics, and engineering. It helps us understand how materials respond to changes in temperature and how they store and release heat. By knowing the specific heat capacity of a substance, we can determine how much energy is required to heat or cool it, which is useful in designing heating and cooling systems. The formula is also used in thermal analysis techniques such as differential scanning calorimetry and thermogravimetric analysis.