acids can be found in your foods. citric acid – oranges, lemons, limes ethanoic acid –...

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Acids can be found in your foods. Citric acid – oranges, lemons, limes Ethanoic acid – vinegar, tomato juice Tartaric acid – grapes Tannic acid – tea Lactic acid – sour milk, yoghurt

They are all around us and are involved in many chemical processes.

YUM, acid!

Other examples of acids: Methanoic acid – insect bites, e.g. bee stings, ant bites Hydrochloric acid – produced in your stomach Lactic acid – produced in body during power exercises

Toilet bowl cleaner

Lead-acid battery

Do-it-yourself cleanersMake a cleaner out of vinegar, baking soda and lemon juice!http://msucares.com/pubs/infosheets/is1436.htm

Hydrochloric acid, HCl Sulphuric acid, H2SO4

Nitric acid, HNO3

Many naturally-occuring acids, e.g. citric acid in oranges, are sometimes known as organic acids.

The other group of acids is called the mineral acids. Most of these are man-made, e.g. sulphuric acid.

A substance which produces hydrogen ions, H+, when it is dissolved in water

All acids produce hydrogen ions, H+, in aqueous solution.

All acids contain hydrogen ions. BUT, not all compounds containing hydrogen

are acids.

Acids have a sour taste. The word ‘acid’ comes from a latin word ‘acidus’, which

means sour. Acids are hazardous.

Irritants Acids change the colour of indicators.

Acids turn blue litmus red – a simple test for acid. Acids dissolve in water to form solutions that

conduct electricity.

1. Acids react with reactive metals to form hydrogen and a salt.

Test for the presence of hydrogen A burning splint is brought near the mouth of the test tube. If hydrogen is present, it burns with a ‘pop’ sound.

Acids react with carbonates and hydrogencarbonates to produce carbon dioxide gas

Test for the presence of carbon dioxide The gas is bubbled through limewater. If carbon dioxide is present, a white precipitate is formed.

React with metal oxides and hydroxides to from a salt and water.

Neutralisation reaction

Acids are stored in glass, plastic jars or clay pots.

Acidic foods are not usually stored in metal containers because metals can react with acids.

Acid Bath Murder

http://www.discoverychannel.co.uk/web/crime-museum-uk/episode-guide/acid-bath-murder/

Examples of acids Definition of an acid Properties of acids

Acids have a sour taste. Acids are hazardous. Acids change the colour of indicators. Acids dissolve in water to form solutions that conduct

electricity. Chemical reactions of acids

Test for gases: Hydrogen and carbon dioxide

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