Whether they are low or high, what do heat capacity and specific heat say about a substance?
All merchandise we find in stores have a price. The more money we put up, the more we can buy, either quantity-wise or quality-wise. Maybe a set of kids’ watches costs $30, but a single men’s luxury watch costs $300! Also, as we buy more of a certain item, our bill is surely going to go up!
Similarly, all substances have a heat capacity, that is a required amount of heat to raise the temperature of the substance by one degree Celsius. Some substances have a higher heat capacity than others, so they require more heat to experience a rise in temperature. Sometimes, also, a substance’s required heat input can be larger than that of another simply because it has a larger mass.
Sometimes in the world of money, however, it doesn’t matter how much of something we have. Let’s say you want to purchase a few souvenirs at a gift shop in England, but first you need to convert your U.S. dollars to British pounds. Although you will need to shell out more money because you are buying several products, the number of pounds you get per dollar will ultimately stay the same.
Specific heat is the required amount of heat per unit of mass to raise the temperature of a substance by one degree Celsius, and it works in a similar manner. The specific heat of a substance does not depend on its mass, remaining the same whether 1 gram or a kilogram is involved.
- It takes 243.5 J to heat 36 grams of a substance from 45 °C to 65 °C. What is its specific heat in J/g·°C? Use the formula q = m × c × ΔT (q = heat energy, m = mass, c = specific heat, ΔT = change in temperature).
Research: What substance has the highest known specific heat at room temperature? You may use the link provided in the "Resources" section.
- Each of the following substances have a different required heat input to raise their temperature by 5 degrees Celsius. Order them from least to greatest required input: 5 grams of solid copper, 5 grams of solid aluminum, 50 grams of solid aluminum. Look up the specific heats of the substances if necessary, or use the link in the "Resources" section.
- What might be some useful applications of a substance with a heat capacity and specific heat that are high? low?