Exploring heat


The first session deals with the earliest historical ideas about heat through fire.
Exploration of mass change of burning of a fuel (wood) with burning magnesium or copper.
ICT link between respiration and burning
Oxygen in air.
Air as a mixture of gases.
Molecules of oxygen, sucrose or glucose. carbon dioxide and water.
Wikipedia - heat
The history of heat began when early man made fire and tried to make sense of what fire was. The concept of fuel is embedded in the concept of fire. In the 1718, Stahl characterised phlogiston as something that is set free on burning. Another biography of Stahl. Lomonosov in 1753 concluded that phlogiston did not exist by weighing heated metals. Lavoisier's discovery of hydrogen in 1783 put paid to the phlogiston concept for many scientists. Caloric as a substance explained much about heat transfer. Joule's work (1843) on the mechanical equivalent of heat linked work to heat.
Phlogiston theory allowed chemists to bring explanation of apparently different phenomena into one joined-up structure: combustion, metabolism and formation of rust. The recognition of the relation between combustion and metabolism helped scientists to recognise that the metabolism of living creatures and combustion can be understood in terms of fundamentally related chemical processes
The second experiment is a re-enactment of heat measurement through the use of a mock up of an ice calorimeter. In the UK, children aged 11-14 have to understand the relationship between burning and respiration.
Latent heat
Structure of solid and liquid water
Children's Ideas:
Calorimeters including ice calorimeter

The third session looks at the passage of heat from a hot block of metal to ice in an insulated beaker. Coins can be used as the metal block to connect to everyday life. Learners will be asked to consider explaining it in terms of caloric.
This does not have to include measurement, since the ice will melt, but a thermometer in the ice can be used to show that the ice will stay at zero degrees C as long as there is ice left.
If water is used in place of the ice, the temperature increase will indicate the passage of heat.
Heat and thermal energy
Heat and particle vibration
Caloric as a substance explained much about heat transfer.

The fourth session works on generating heat from mechanical energy.