TEMPERATURE AND SPECIFIC HEAT
What exactly is heat? When you touch something warm, you feel heat, but what
is that? Technically, heat is defined as the flow of energy from a body at a higher
temperature to one at a lower temperature. If a particular sample of a substance
experiences an increase in temperature, then you can say that particular sample
has experienced an increase in heat content. So what exactly does temperature
measure? Temperature measures the average kinetic energy of molecules in a
sample; as the molecules in a sample move more quickly, the temperature of that
sample increases.
For certain substances, the addition of a large amount of heat will have only a
small effect on their temperature, while for other substances, the addition of a
small amount of heat will have a dramatic effect on their temperature. The heat
capacity of a substance refers to the amount of heat it must absorb for its
temperature to be raised 1°C. Different substances have different heat capacities,
and the heat capacity of a substance is described by its specific heat. The
specific heat of a substance is the heat capacity of 1 gram of the substance.
Here’s an equation that puts together all of the terms we just reviewed.
q = mcΔTIn this equation:q = heat
m = mass
c = specific heatΔT = the difference between initial and final temperatures (Δ means change
or difference)