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Measuring temperature - freezing point

Description

A presenter based at the British Antarctic Survey named Liz explains that room temperature is typically 20掳C whereas their cold room, where ice core samples are stored, is maintained at -26掳C. The freezing points of water (0掳C), shampoo (-3掳C), olive oil (-12掳C) and sunflower oil (-17掳C) are then measured by Liz. Frozen food is usually kept at -18掳C and Liz explains that a frozen chicken must be defrosted to room temperature before being cooked. This represents a rise in temperature of 38掳C (-18掳C to 20掳C).

Classroom Ideas

Students could be given test tubes with various different liquids and go on to explore the freezing points or thawing time for each. Based on the ideas presented in this clip, students could make predictions about which liquids they think will freeze or thaw first. The experiment could also be turned into a challenge. For example, 鈥渇ind the liquid with the highest freezing point鈥.