Specific Heat

Specific heat is the amount of heat required to make one gram of something 1 oC hotter.

Remembering that heat capacity is the amount of heat required to make something 1 oC hotter we can see why specific heat can be more useful. By separating out the mass of the object we can begin to think of things in more general terms. Simply put, thinking in terms of specific heat allows us to compare cocoa to toast in general, rather than having to speak of the heat capacities of a particular cup of cocoa and a particular stack of toast.

The specific heat of cocoa is much larger than that of toast, and therefore if you are given a choice between similar amounts of toast and cocoa you know that the cocoa will do a better job of warming you.

Much of the work that is done in chemistry to measure heat involves water. It is therefore useful to know the specific heat of water. The specific heat of water is 1.00 calories/g oC or 4.184 Joules/g oC. These two numbers are actually the same value. Joules is the standard metric unit for energy (and therefore for heat). Calories is a unit that was invented by chemists to make measurement of heat easy. Many chemists use both units, many others use only one of these units. Your instructor will tell you what they expect you to know, and this text will provide sample problems using each unit so that you will have an example to follow no matter which unit your instructor prefers.
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