Ph

Introduction:
Ph is a measure of the acidity or basicity of a solution. Solutions with a Ph less than 7 are said to be acidic and solutions with a Ph greater than 7 are basic.

Materials:
-Distilled water               -Vinegar
-Milk                               -Strips (universal indicator paper)
-Wine                              -Ph-meter
-Lemon                           -Acetic Acid
-Tomato                          -Tongs
-Coffe                             -8*100 Ml Beaker                                      
-Carbonated beverage    -2 Clock Glass
-NaOH solution             -1*100 Ml Beaker
-HCl solution                  -5 test tubes
-Soup solution                -Funnel
-Test tube rack               -Graduated Cylinder
-10 Ml Pipet                   -Coca Cola
-Distilled water              -Soy milk

Objetives:
-Measure different Ph values of organic and inorganic solutions.
-Prove different metods of measuring Ph.

Procedure:
-Cut the lemon and tomato.
-Put this in two clock glasses.
-Take a piece of indicator paper and put this in the solution for a least 20 seconds.
-Remove the indicator paper.
-Compare its colour with appropriate colour chart.
-Record your results in a result table in your workssheet for compare with the class.
TABLE:

Lemon-2 acidic
Tomato-4 acidic
Milk-7 neutral
Vinegar-2 acidic
Wine-3 acidic
Coca Cola-2 acidic
Distilled water-7 neutral
NaOH-12 basic
HCl-1 acidic
Soap Solution-8 basic
Soy Milk-7 neutral




-Prepare a test tub rack with 5 test tubes (cleaned with distiller water).
-Mark the tubes with the labels; A, A1, A2, A3 and B.
-Add 10Ml of lemon juice to tubes A and B.
-Take the A tube and put 5Ml of its lemon juice to test tube A1.
-Take the A1 tube and put 2,5 Ml of its lemon juice to tube A2.
-Take the A2 tube and put 1,2 Ml of its lemon juice to tube A3.
-Add distilled water to each test tube until it has the same volume as test tube B (10Ml).
-Calculate the concentration and Ph of each test tube:
      Concentration   Ph
B-       50%             2,7
A1-     25%             2,8
A2-     13%             3,08
A3-     12%             3,08
A-       1%               3,08
The test tube B is the most acidic.

Observations:
Questions;
1.Which of the solutions gave an acid Ph?
Lemon,tomato, vinegar, wine, Coca Cola and HCl.
2.Which of thhe solutions was alkaline?
Soup solution and NaOH.
3.Which of the solution were neutral?
Milk and destilled water
4.How does a Ph of 3 differ from Ph of 4 in terms of H+ concentrations?
The ph3 has nine times more protons than the ph4
5.In the second part of the experiment, you have compared the Ph of the same product in different concentrations. In this case explain:
  a.Which is the dependent variable?
     Is the Ph
  b.Which is the independent variable?
      Is the concentration
  c.Which is the problem that we want to solve?
      Can lemon juice concentration variated the concentration?
  d.Which is the control of the experiment?
      B, because is only lemon and we can compare
6.Which Ph do you think that gastric juices might have? Why? Do you think that intestinal Ph has the same Ph? Why?
     Acid because hace acid cloridric.
7.Which Ph do you think that blood might have? Why?
Blood have 7,2 is neutral.
8.What is acid rain? Which are the consequences in the ecosystems and how is its fornation pattern? Is rain in Barcelona acid or Alkaline?
Is a rain that is unusually acidic, meaning that it have a low pH.
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.
Rarely happens in Barcelona, but if this happens is in industrial areas like Forum.