Chemistry%20Project:%20Acids%20and%20alkalis

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Chemistry ProjectAcids and alkalis

• The aim of the project
• To know more the details of alkalis and acids.

• Other details
• Experiment
• Results
• Web Site s version

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Group member

• Lee Keng Ho (21)
• Lee Ho (20)
• Lam Chung Wai (14)
• Wong Kin Sang (38)
• Chan Shing Ho (6)
• LAM Ka Shing (16)

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What is soil?

• Involves many nutrients and nature chemicals.
• To provide the nutrients for helping grow plants.

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Experiment 1 Testing the soil

• beaker (-to store the water and soil to test
  the alkalis and acids)
• glass rod (use to stir the liquid)
• soil (main substance in the experiment)
• water (to dissolve the acids by the soil)
• pH paper (test the alkalis and acids)

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Experiment 1 Testing the soil

• Step 1
• Drop some soil in to the beaker.
• Step 2
• Use the glass rod to stir the soil and water in
  the beaker.
• Step 3
• Put pH paper into the beaker to test the alkalis
  and acids.

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Experiment 1 Testing the soil

• The figure of making the experiment .

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Experiment 1 Testing the soil

• Results
• The pH value of the soil is
• That means the soil ia neutral state.
• The ph colour is orange.

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Experiment 1 Testing the soil

• Main Details Of Acids Base pH paper
• pH 1 very strong acids
• pH 2-6 weak acids
• pH 7 neutral
• pH 8-13 weak alkali
• pH 14 very strong alkali

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What is the main use of fertilizer

• (1) Be a refractory material.
• (2) Be nutrient in plant.
• (3) Be an additive into the forage of domestic
  animal.
• (4).Used to prevent fire with paper nad wooden
  things.

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What is the advantage of fertilizer?

• To Get a good condition in soil to let plants
  grow its best!
• To recruit the leakage of the soil.

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What is the weaknesses of fertilizer?

• Make dirty in water.
• Some of chemicals may damage the sir.

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Experiment 2 Making fertilizer

• Procedure
• Step 1
• Place about 10cm of ammonia solution in a conical
  flask.
• Step 2
• Add 2-3 drops of indicator solution ( methyl
  orange)./ Add pH paper
• Step 3
• Fill a burette with a sulphuric acid.

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Experiment 2 Making fertilizer

• Procedure
• Step 4
• Slowly add the acid to the conical flask until
  the indicator changes colour from yellow to
  red.(if we use the pH paper , it changes colour
  from blue to red )
• Step 5
• Repeat, using the same volumes of alkali and acid
  but without any indicator .
• Step 6
• Place some of the neutral solution in the
  evaporating basin. Heat gently to evaporate the
  solution.

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Experiment 2 Making fertilizer

• Procedure
• Step 7
• Collect the solid into the test tube.

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Experiment 2 Making fertilizer

• Results
• The apperance of fertilizer is prersent. It s a
  white solid.

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• apparatus
• Plant material ( the leaves of your growing
  plant)
• Extraction solvent (acetone / petroleum) 11
• Developing solvent (acetone / petroleum) 19

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• Step 1
• Prepare strips of chromatography paper of the
  right width so that each can be hung freely in a
  boiling tube without touching the wall. The
  length of the paper should be trimmed according
  to the level of solvent to be put into each
  boiling tube.
• Step 2
• mark an origin for spotting on the paper about
  2cm from the lower edge of the paper.

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• Step 3
• Transfer appropriate amount of the developing
  solvent into the boiling tube ( a depth of not
  more than 1.5cm ). Stopper them for equilibrium.
• Step 4
• preparation of pigment extract
• .Wash leaves and blot dry.
• .Cut leaves into small segments and put into a
  mortar.
• .Grind the tissue in the extraction solvent with
  a pestle to extract the pigments.

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• Step 5
• By means of a capillary tube spot the extract
  onto the origin marked on the paper strip and
  allow it to dry.
• Step 6
• Repeat the spotting and drying processes obtain
  a small area of concentrated leaf extract.

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• Step 7
• Pin the paper onto the lower surface of the cork
  and insert the paper into the boiling tube. The
  solvent should cover the lower end of the paper
  but without touching the spot.
• Step 8
• Allow the chromatogram to develop until the
  solvent front has moved up for 10cm or more.

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• Step 9
• Take out the chromatogram, mark the solvent front
  and allow the chromatogram to dry in air.
• Step 10
• Use pencil to circle each spot.
• Step 11
• Identify the pigments by their colors on the
  chromatogram.

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Experiment 3 Extraction and separation of leaf
pigments by paper chromatography

• Results
• The color of pigments change from yellow to pale
  green.

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Question

• Are there any other way to test acids?
• hair
• ________

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Web Site of our Project

• http//www.angelfire.com/electronic/chemistry1/ind
  ex1.html