Change

The experiments in this section cover the concepts of physical and chemical change. Examples include activities which show that chemical change results in new substances with different properties from the starting materials.

While we are still at an early stage with this website it's probably more useful to look at the page with our complete list of experiments in alphabetical order. See the list on About this website.

We are starting with GCSE-level experiments.
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Experiments

• The alcohol ‘gun’

  A demonstration of the large energy changes that occur during the combustion of alcohols.

• Fat-pan fire!

  A fat-pan fire is used to demonstrate the conditions required to start combustion.

• The cornflour ‘bomb’

  A small explosion, caused by the rapid combustion of cornflour, blows the lid off a tin.

• Chocolate and Egg

  By comparing the effects of heat on chocolate and on egg white, students are introduced to the difference between physical change and chemical change.

• The real reactivity of aluminium

  In this demonstration the oxide coating on aluminium foil is removed with sodium hydroxide and mercury(II) chloride. The exposed aluminium reacts rapidly with oxygen in the air to reform the oxide.

• The copper envelope

  Copper foil is folded and heated. The outside reacts with oxygen to produce the oxide while the inside remains unchanged.

• The causes of rusting

  In this class experiment, students subject iron nails to variety of conditions to find out which are necessary for rusting to take place.

• How much air is used during rusting?

  In this class experiment, students set up iron wool to rust in a test tube full of air inverted in a beaker of water. This can be used to find the percentage of oxygen in the air.

• The change in mass when magnesium burns

  Magnesium of a known mass is reacted with oxygen in a crucible to prevent loss of the product. The crucible is re-weighed at the end to show that there is an increase in mass. This experiment can also be used to find the formula of magnesium oxide.

• The combustion of iron wool

  In this quick demonstration, iron wool is heated on a simple ‘see-saw’ balance and the increase in mass is shown.

• A solid-solid reaction

  Solid lead nitrate and solid potassium iodide are shaken together in a small jar. They quickly react to make yellow lead iodide.

• Diffusion in liquids

  Students place a crystal of lead nitrate and a crystal of potassium iodide into a petri dish of deionised water. These dissolve, diffuse and react to form yellow lead iodide.

• The position of iron in the reactivity series

  This experiment involves a series of reactions that help identify the positions of iron in the reactivity series.

• The thermite reaction

  In this spectacular experiment iron(III) oxide is reduced to iron by aluminium.

• Experiments with hydrogels – plant water storage crystals

  Students investigate plant water storage crystals, a product that contains hydrogels.

• The reaction of magnesium with copper(II) oxide

  This experiment can be used to confirm the relative positions of magnesium and copper in the reactivity series.

• Experiments with hydrogels – hair gel and disposable nappies

  Students investigate two products that are readily available and contain hydrogels.

• The fractional distillation of crude oil

  This experiment simulates the industrial fractional distillation of crude oil in the laboratory.

• Developing a glue

  This experiment shows how to make a glue from soured milk and a base.

• Cracking hydrocarbons

  A mixture of alkanes is cracked by passing the vapour over a heated catalyst. Tests for unsaturation are used to show the presence of alkenes in the products.

• Heating Group 1 metals in air and in chlorine

  This experiment demonstrates the reactions of Group 1 metals in air and in chlorine.

• Reaction of zinc with iodine

  In this experiment students note the differences between a metal and a non-metal, and their reaction to form a metal salt.

• Neutralisation – ‘curing acidity’

  Simple experiment to show the pH and temperature changes when an acidic solution is neutralised by the addition of slaked lime (calcium hydroxide) or limestone (calcium carbonate).

• Extraction of iron on a match head!

  A mini-scale experiment to extract iron by carbon reduction.

• Iron and sulfur reaction

  Two elements, iron and sulfur, react together to form a new compound.

• Ammonium dichromate volcano

  An eruption of green ash, sparks and steam occurs as ammonium dichromate(VI) decomposes exothermically.

• Money to burn

  A striking demonstration that different fuels have different ignition temperatures.

• Spontaneous exothermic reaction

  The delayed reaction between potassium manganate(VII) and glycerol.

• Exploding balloons

  Demonstration experiment involving exploding balloons containing mixtures of hydrogen and oxygen in varying proportions.

• Identifying the products of combustion

  A simple demonstration to identify the gaseous products of the combustion of hydrocarbons.