Sunday, 26 April 2015

Metals, acids, reactivity and energy

Reacting metals with an acid produces Hydrogen gas. These reactions are also exothermic, the energy released in the reaction is related to the relative reactivity of the chemicals used.

Equipment

Samples of powdered metal.
Hydrochloric, Sulphuric and Nitric acids - 1 molar
Boiling tubes
Top pan balance - 0.01g resolution
Digital thermometer - 0.1 degree C resolution
Measuring cylinder - 10 ml

Method

Measure 10ml of acid into the boiling tube.
Measure 0.5g of the metal powder.
Record the temperature of the acid using the digital thermometer, then add the metal powder to the acid.
Record the highest temperature reached.
Repeat for each metal, with each acid.

Risks

Some reactions will produce a lot of energy and get very hot so care should be taken when touching the bottom of the boiling tube. The reaction evolves Hydrogen gas which can cause the liquid to bubble up the boiling tube and spill over. care should be taken when clearing up spills. Goggles should be worn at all times during the experiment.