EXPERIMENT 2

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EXPERIMENT 2

• CHEMICAL REACTIONS AND EQUATIONS II

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PURPOSE

• To investigate the acid-base behaviour of some
  metal hydroxides and to examine some
  oxidation-reduction reactions involving metals

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Displacement Reactions Involving Addition of
OH-(aq) and NH3(aq)
Place 3-5 drops of each reagent into separate,
labeled tubes.
Add 1 drop of 1 M NaOH to each, mix well and
observe the formation of the metal hydroxide
precipitates.
Add 1-5 drops additional 6M NaOH to each of the
test tubes.
Based on your observations, classify each of the
metal hydroxides as basic or amphoteric.
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In basic media the pH paper turns BLUE .
To test pH, dip the glass rod into the solution
then touch the pH paper. Never put the pH paper
into the solution.
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In acid media the pH paper turns RED .
Predict what will happen if acid is now added to
each of the six samples.
Add an excess of 6 M HNO3 to each of the test
tubes.
Mix the contents thoroughly and record your
observations.
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Continue as described in your lab manual

• Formation of Ammine Complex Ions
• Oxidation-Reduction Reactions
• Metal acid
• Metal metal ion