How does changing the amount of water in a beaker affect the rate at which its temperature rises? A simple experiment in which students heat two different amounts of water and measure the temperature rise. Heat energy and temperature are related, but they aren’t the same thing!
Heat Energy and Temperature Rise – Water and Oil
If you supply an equal amount of heat energy to an equal mass of water and oil will they both increase in temperature by an equal amount?
SPOILER ALERT!! The second practical activity shows students that if two different substances absorb the same amount of heat energy, they won’t necessarily increase in temperature by the same amount. Water requires a relatively large amount of energy to raise its temperature by a given amount compared to most other substances. It also has to lose more heat energy to drop its temperature by a given amount than most other substances.
This is partly the reason that inland areas far away from the ocean, like Alice Springs in central Australia for example, can reach a top temperature of more than 20°C above the overnight minimum, whereas areas near the ocean don’t fluctuate in temperature anywhere near as much on any given day. The ocean water absorbs energy during the day, but its temperature doesn’t rise all that quickly, and so the surrounding air also doesn’t change all that much on any given day. Towns like Gladstone and Rockhampton, which are at about the same latitude as Alice Springs (and the beautiful Airlie Beach just a little further north) may only go from 22°C to 30°C on any given day.
That’s Spiro on a shoot at the magnificent Whitehaven Beach, Whitsunday Island, Queensland (just off the coast from Airlie Beach). LEM were there shooting part of the Shedding Light on Light series, which in part covers electromagnetic waves and heat radiation.
Determination of the Specific Heat Capacity of Water.
The layout of this prac makes it easy for students to calculate the specific heat capacity of water. My students typically find a value that is within 10% of the accepted value.