Limestone Deposit Removers - Acidic Household Cleaners

3 Limestone Deposit Removers - Acidic Household Cleaners 

Problem The removal of limestone with an acid solution may be considered by the students as a form of destruction - the object of the lesson is to uncover this misconception and to point out that the removal of calcium deposit is a chemical reaction which forms new substances. This chemical reaction is in fact an acid— base reaction, which can be described with a proton transfer from hydronium ions to carbonate ions to form a salt solution and gaseous carbon dioxide. 

Material Beakers, test tubes calcium carbonate powder, dilute hydrochloric acid, household limestone deposit remover, candle. 

Procedure Place a little amount of calcium carbonate powder in the beaker and cover with a few ml of hydrochloric add. After a short while, insert a burning candle into the beaker. After reaction is over, evaporate the remaining solution. Repeat the reaction with limestone deposit removers (acidic household cleaners) check the type of acid from its label and interpret the information. 

Observation A lively gas development begins, the lit candle extinguishes in that gas carbon dioxide. A white substance remains after evaporation calcium chloride. 

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