test for anions present in various salts.

METHOD:

1. potassium chloride salt was put in a test tube
2. then nitric acid was inserted in the same test tube
3. any observation seen was recorded in a table
4. more nitric acid was then inserted until the salt dissolved
5. distilled water was then added
6. Silver nitrate was added using a new pipette. Results were then recorded
7. potassium chloride was then inserted in another test tube
8. a few drops of hydrochloric acid were then inserted in this new beaker
9. results were recorded
10. more hydrochloric acid was then inserted until the slat dissolved
11. distilled water was then inserted sand mixed well
12. a few drop were added of barium chloride solution and results were recorded
13. Steps from 1 -8 were repeated for the other remaining salts.

RESULTS TABLE

CONCLUSION

From the result I can inform that - The salts that gave white precipitate when the acids were inserted (silver nitrate and nitric acid) there were the metal chlorides and carbonates.  The sodium sulphate reacting with hydrochloric acid and barium chloride produced a white precipitate, informing us that there are negative ions present in this salt. The lead carbonate reacted with nitric acid and hydrochloric acid producing bubbles which indicates that a gas was given off.

When the salts were added to silver nitrate they all generally produced precipitates informing that they were insoluble suspensions.

• From my results I discovered that when the chlorides, both metals potassium chloride and iron chloride were inserted in the solution of nitric acid followed by a few drops of silver nitrate a precipitate was formed. This thus informed us that chloride anions were present in both metals. This also notifies us that if any  salt or test are carried out to identify the negative ion present, are inserted in the test of anions, for example if a slat is added to nitric acid followed by silver nitrate and a white precipitate is formed then this will inform us, that there are negative chloride ions present, therefore this solution will have chloride negative ion present.

• The reaction of the sodium sulphate metal when inserted in the different solution to test the anions present, I discovered that the sodium sulphate when added to hydrochloric acid followed by barium chloride, a white precipitate was formed. This informs us that negative sulphate ions are present. Therefore if any salt or test is carried out to identify the anions present, is inserted in the hydrochloric acid solution followed by the barium chloride solution , if the solution turns into a whit precipitate then this will be known that there is a sulphate anion present in the salt. Resulting the slat to have a negative sulphate ion present.

• Form the result of the both carbonates, the calcium carbonate and lead carbonate I can summarise the following. When they were inserted in each of the different solutions the calcium carbonate formed white precipitates of each of the solutions added. Although when added to the hydrochloric acid it formed bubbles and fizzed. The lead carbonate formed bubbles and fizzed when both nitric acid and hydrochloric acid were inserted in to it. From these both metals results, I acknowledged that the both metals inserted in hydrochloric acid fizzed and bubbles were given off which was the carbon dioxide gas released. Therefore informing me that there was a negative ion present, which was the carbonate ion. further more if any salt or test was carried out to identify the anions present , if   hydrochloric acid or nitric acid were inserted into it  and  the solution formed bubbles/fizzed, then the negative ion present here will be carbonate. Thus the salt will then have a carbonate anion present in it. When carrying out experiments to see which negative ion is present, if the mixture fizzes when nitric acid or hydrochloric acid is inserted then you can automatically identify it has a carbonate ion present.

EVALUATION

In this experiment I have achieved my aim in identifying anions present in several salts.

My experiment could have improved if I had followed the procedure much better.

I had difficulty in this experiment in realising the reactions taking place in the test tubes I overcame this problem by focusing carefully and consulting with my partner in the reactions occurring.  I have learnt that when an atom absorbs light or when an atom bonds an electron can be gained or lost and what is left is an ion. If the ion gains an electron it has become a negative ion and if it looses an ion it becomes a positive ion. This is because the balance of the electrons protons is distributed.