ACIDS AND BASES

Acids have the following properties

  • Contain H+ ions

  • Taste sour

  • Have a pH between 1 and 7

  • Turn blue litmus red

  • Are corrosive (eat away) metals

  • Found naturally in fruits and some foods

Bases have the following properties

  • Contain OH- ions

  • Taste bitter

  • Have a pH between 7 and 14

  • Turn red litmus blue

  • Are corrosive (eat away) metals

  • Are used often in cleaning products and often have a slippery feel


pH SCALE AND UNIVERSAL INDICATOR

pH stands for the power of hydrogen

Universal indicator changes based on pH

This diagram shows the relationship between pH and the colour of the Universal indicator solution


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LITMUS INDICATOR

Litmus is an indicator that only has 2 colours - red or blue

Red litmus will turn blue in a basic solution

Blue litmus will turn red in an acidic solution



Litmus is made from a lichen found in South America called Roccella Tinctoria, it is the oldest pH indicator known to man

for more information go to http://en.wikipedia.org/wiki/Litmus

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