- Although heat and temperature are used interchangeably, heat and temperature are not synonymous. Heat is a form of energy that is measured by temperature. Heat is used in chemical reactions to give energy to reactants. Chemical reactions lose energy to the system in the form of heat, which is described as entropy in the Laws of Thermodynamics.
- Temperature is used to measure the amount of heat in an object. Temperature has several notations such as Celsius, Fahrenheit and Kelvin. For heat capacity, the temperature is usually expressed in Celsius. For heat capacity, the temperature of an object rises by the absorption of heat. Different objects can absorb more heat than others before there is a change in temperature. For instance, metals become very hot quickly when heat is absorbed. The heat capacity of metals is therefore very low, since the temperature increases with only a small amount of heat introduced.
- Calorimetry is the mechanism used by scientists to study heat capacity. Calorimetry uses two objects together to measure the temperature and determine heat capacity of different elements. The test is conducted by pouring a specific weight of hot water into a Styrofoam cup. Then a cooled object like iron is dropped into the cup. When the heat reaches equilibrium, the scientist measures the temperature of the iron object and the temperature of the water. The amount of heat absorbed by the object and its relative temperature determines its heat capacity.
- The equation for heat capacity is as follows:
Q=c * m * <change in temperature>
Q is the amount of heat added to the system. The letter "m" is the mass of the object. Finally, the "<change in temperature>" is the difference between the temperature before the objects were connected and the temperature measured after equilibrium.
The letter "c" is the specific heat of the object. To find "c" from the equation above, the calculation becomes:
c= Q / (m * <change in temperature>) - Water is an integral part of life. Water has the highest specific heat of 4.186 joule/gram °C. This makes water an important part of biological systems since it is able to absorb high amounts of heat without having a temperature change.
Heat
Temperature
Calorimetry
The Equation
Water
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