Acidic Environment

9.3 The Acidic Environment

9.3.1
9.3.1.1 Classify common substances as acidic, basic or neutral
|Acidic |Basic |Neutral |
|Stomach Acid(1-3) |Soaps (10) |Pure water |
|Vinegar (2-3) |Cleaning products (8-14) |Ethanol |
|Citrus fruits (3-5) |Sodium carbonate (washing soda 10) |Table Salt |

http://www.chem.unsw.edu.au/highschool/files/acid.pdf
http://angel-patti03.tripod.com/id2.html
http://www.visionlearning.com/library/module_viewer.php?mid=58

9.3.1.2 Identify that indicators such as litmus, phenolphthalein, methyl orange and bromothymol blue can be used to determine the acidic or basic nature of a material over a range, and that the range is identified by change in indicator.
[pic]
(pic: (http://www.hsc.csu.edu.au/chemistry/core/acidic/chem931/image1.gif)

Litmus: A dye that changes colour around the neutral range.
Phenolphthalein: A synthetic indicator that changes colour in the basic range.
Methyl orange: A synthetic indicator that changes colour in the acidic range. Bromothymol blue: A synthetic indicator than changes colour around the neutral range.

Each of the indicators above and a combination of them can be used to determine the acidity/basicity of a substance.

http://www.chem.unsw.edu.au/highschool/files/acid.pdf
http://www.visionlearning.com/library/module_viewer.php?mid=58
http://www.users.on.net/~rowlo/chem/acidicenvironmentsummary.doc

9.3.1.3 identify and describe some everyday uses of indicators including the testing of soil acidity/ basicity
Indicators are used to test pH of soils e.g. barium sulfate. The optimum ph range is needed to grow plants so the pH of soils needs...