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CHEMISTRY

Practice #1 "Chemical Reactions"

The purpose of this practice is to recognize the chemical properties of some substances.

The materials used were:

*Bunsen burner

*Beaker

*Test tube

*Test tube tongs

*Spatula

*Zinc (granalla)

*Magnesium (tape)

*Copper (wire)

*Hydrochloric acid

*Silver nitrate

*Barium chloride

*Sodium sulfate

*Lead nitrate

*Potassium iodide

What we did:

1.we added 20 drops of HCl and a little bit of zinc granalla into the test tube.

2.With the crucible tongs we held a piece of Mg tape and lighted up with the bunsen burner

3.we took a small piece of copper wire and inmersed in a solution of 20 drops of silver nitrate.

4.Poured 20 drops of barium chloride and 20 drops of sodium sulfate into the same test tube.

5.We put 20 drops of solution of lead nitrate and 20 of the potassium iodide solution.

The results were:

1. the solution was efervescent, it started to emit bubbles; then the little pieces of zinc started to disappear.

2. the piece og magnesium emmited a resplandescent white light

3. the copper wire started to loose a little pieces of itself

4.the solution didn´t have any color, and then reacted and changed to be a white substance

5. the substances reacted and the solutions changed to yellow color.

Here are the formulas or chemical equations:
HCl + Zn --> ZnCl2 + H2
Mg + O2 --> 2MgO
AgNO3 + Cu --> Cu(NO3)2 + 2Ag
BaCl2 + Na2SO4 --> BaSO4 + 2NaC
Pb(NO3)2 + 2KI --> PbI2 + KNO3