Drain Cleaner - an Alkaline Household Chemical

Problem Young people are familiar with acids as substances which can decompose other materials. They are usually not aware, though, that hydroxide solutions are also aggressive substances which should not be placed near the skin but espedally not near the eyes. The decomposing properties are mainly used to dissolve and remove organic leftovers from the kitchen or bathroom. The 

Material Beakers, thermometer, glass rod sodium hydroxide, drain cleaner, wool, paper. 

Procedure Cover several pieces of sodium hydroxide with a few ml of water in a beaker and stir with the thermometer. Add wool and paper pieces to the solution and stir well. Repeat the test with drain cleaner, and interpret the label on the bottle. 

Observation Sodium hydroxide dissolves and the mixture gets very hot, wool and paper pieces dissolve in the concentrated solution. The same happens in the drain cleaner solution. 

Tip The remains of the solution should be thoroughly rinsed with a lot of water. Even diluted amounts of hydroxide solutions are dangerous because when the water evaporates, high concentrations of sodium hydroxide are produced and cause holes in clothing. 

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