Post on 07-Jan-2016
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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. 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