Precipitation, silver chloride, silver nitrate and sodium chloride.

         Silver nitrate + sodium chloride = silver chloride + sodium nitrate

Method

I carefully measured out 10cm3 of silver nitrate using a 10cm3 measuring cylinder (accurately). I did this over a sink and poured the silver nitrate into a clean beaker.

I measured out 20cm3 sodium chloride solution using a 25cm3 measuring cylinder.

Then I slowly added 10 cm3 of sodium chloride solution into a beaker containing the silver nitrate. I used a glass rod to sir the solution.

I saw a precipitate of solid crystals of silver chloride.

Then I added sodium chloride solution still in the measuring cylinder slowly until no more precipitate formed.

I wrote my name on the piece of filter paper so I would know it was mine.

Then I weighted the filter paper and recorded its mass.

This is because; the silver chloride is insoluble in the water and may be separated by filtration. I filtered the solution into a beaker.

I washed the precipitate in the filter paper with distilled water to remove soluble sodium nitrate and any unreacted silver nitrate and sodium chloride.

Then the liquid filtrate of sodium nitrate in the beaker is disgarded.

I kept the residue of silver chloride crystals on the filter paper and left it to dry.

Measurements

AgNO3 (aq) + NaCl (aq)       =      NaNO3 (aq) + AgCl(s)

1 mole of AgNO3 is required to produce 1 mole of AgCl

So 108 + 14 (3 * 16) g AgNO3 is required to produce 108 + 35.5g AgCl

So 170g AgNO3 is required to produce 143.5g AgCl

So 1000cm3 solution contains 170g AgNO3

So 10cm3 of a 0.1 molar solution of silver chloride contains 0.17g AgNO3

So 0.17g of silver nitrate was used

Theoretical yield 0.17 * 143.5g = 0.1435g

                                        170

Actual yield = 0.95g

Percentage yield = 0.95g * 100  

                               0.1435g

                              = 664%

Results

Mass of silver chloride + filter paper = 0.95g

Mass of filter paper = 0.85g

Mass of silver chloride produced

I.e. actual yield of silver chloride = 0.15g

Evaluation

The only problem I had was when the solid stayed at the bottom of the beaker to overcome which I had to add some water to get the solid on to the filter paper.

 

Vocational Aspects

The major uses for silver nitrate in industry are:

Starting materials for the production of silver electronic materials

Photographic films

Starting materials for manufacture of other silver chemicals such as silver chloride, silver acetate, silver sulphate, etc.

Medicinal for bacterial control.

Catalyst manufacture

Mirrors

Silver chloride’s preparation is important commercially for the photographic industry. Silver chloride also has interesting optical properties as it can be made transparent. It also is cement for glass.

Observation during procedure

During the experiment, I was observed when I added the silver nitrate to the sodium chloride it started to react and fizzed because of this reaction we produced silver chloride and sodium nitrate. I collected all of my silver chloride I did not leave any in the beaker but I collected it on my filter paper.

Summary

In the experiment I prepared silver nitrate by a precipitation reaction between silver nitrate and sodium chloride. I filtered the silver nitrate and calculated the yield.