Indicactor lab

Essay by EssaySwap ContributorHigh School, 12th grade February 2008

download word file, 2 pages 0.0

Downloaded 400 times

What is in each test-tube? What proof do I have of this? Test-tube A: Test-tube A had water in it. I can base this on the fact that it was a neutral, reacting neither to red or blue litmus paper. Phenolphthalein also did not react to this substance. The pH value was 7, neutral, also adding to the proof that this substance was water, because water is neutral. The substance was clear and odorless, and all of these reactions combined led me to my conclusion of substance A being water.

Test-tube B: Test-tube B had spoiled milk in it. The substance reacted to blue litmus paper, and red litmus paper underwent no change. Phenolphthalein did not change, and the pH value was 6, a weak acid. The appearance of this substance was a thick, white liquid that had a horrible odor. These observations led me to my conclusion that substance B is spoiled milk.

Test-tube C: Test-tube C had ammonia in it. The substance reacted to red litmus paper, and it had no effect on blue litmus paper. Phenolphthalein turned a hot pink color very quickly, and the pH value was about 11.5. The substance was clear and had a strong odor to it. These results led me to my conclusion that substance C is ammonia.

Test-tube D: Test-tube D contained lemonade. The substance reacted to blue litmus paper, and red litmus underwent no changes. It had no effect on Phenolphthalein, and its pH value was 3, a strong acid. Knowing that lemons are very acidic, and that the substance was yellow and sweet smelling, I concluded that substance D was lemonade.

Test-tube E: I could not come to a conclusion on what substance E was. It reacted weakly to blue litmus paper, and it did not change red litmus. It had no effect on Phenolphthalein, but its pH value tested as 7. This cannot be correct however, because all acids have a pH value less than 7. The appearance and smell were not of any help, because it was a clear substance with a slight odor I couldn't key in on. So my conclusion is that this substance was an extremely weak acid of some sort.

Test-tube F: Test-tube F contained sodium hydroxide. The substance had a very strong reaction to red litmus and no reaction to blue litmus paper. It had a very strong effect on Phenolphthalein, and its pH value tested as 12+, a very strong base. The substance also had a bitter odor. These results led to my conclusion that substance F was sodium hydroxide, one of the strongest bases that exist.