Do not attempt to perform this demonstration. The combustion of methane is an example of an exothermic reaction. More energy is released when the bonds in the products are formed than is used to break ...

Interactive activity: Changes of state - OCR 21st Century What is the evidence for climate change? - OCR 21st Century How can scientists help improve the supply of potable water?

The film explains the concept of chemical changes, where two or more materials combine to form entirely different substances.

Polanyi took as his subject, “The Transition State in Chemical ... the energy of the reaction must be sufficient to surmount this energy barrier. Hence the plotting of the energy changes ...

All living things depend on millions of chemical ... energy needed to start a reaction. Each enzyme molecule has a special place called the active site where another molecule, called the substrate, ...

starts at the energy of the reactants is equal to the difference in energy between the top of the 'hump' and the reactants The overall change in energy in a reaction is the difference between the ...