A presenter based at the British Antarctic Survey named Liz explains that room temperature is typically 20°C whereas their cold room, where ice core samples are stored, is maintained at -26°C. The freezing points of water (0°C), shampoo (-3°C), olive oil (-12°C) and sunflower oil (-17°C) are then measured by Liz. Frozen food is usually kept at -18°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°C (-18°C to 20°C).

First broadcast:
14 September 2007

Students could make a thermometer using a borrowed conical flask, bung, and a length of glass tubing. This should be assembled and filled with coloured water to halfway up the tube. The marker is then drawn on the tube at room temperature before the thermometer is placed in the sun, shade or fridge to see what effect these changes have upon the height of the fluid in the tube. Students could compare the freezing point of alcohol (in the form of a spirit) and water by putting both into the freezer. Why does the alcohol not freeze?