Energy

Energy

Whenever chemical reactions occur, there are changes in energy. This means that when chemicals get together, things either hot up or cool right off.

Energy transfer can be measured

1) You can measure the amount of energy produced by a chemical reaction ( in a solution ) by taking the temperature of the reagents ( making sure they're the same), mixing them in a polystyrene cup and measuring the temperature of the solution at the end of the reaction.

2) The biggest problem with energy measurements is the amount of energy lost to the surroundings.

3) You can reduce it a bit by putting the polysyrene cup into a beaker of cotton wool to give more insulation, and putting a lid on the cup to reduce energy lost by evaporation.

4) This method works for reactions of solids in water ( e.g. dissolving ammonium nitrate…