The purpose of this lab was to use the general chemical knowledge to identify 10 different unknown solutions. There are two main techniques that were used which are, measuring their pH, and, reacting all of the solutions together. Identifying an unknown solution is an essential skill for anyone who is going to work in a lab because many times, the label might not be accurate, or damaged.
Procedure:
Safety Precautions: Eye protection - Avoid skin contact. Procedure: Ten unknown solutions were obtained in addition to a spot plate and pH test paper. An expectation matrix was constructed. The pH of each solution was measured and labeled from a strong base to a very strong acid. Then, react one of the unknown solution with all of the others and note any visible reaction (change in color or formation of precipitate) that occurs. After that, some the solutions might be identified throughout the …show more content…
The way that they identified was to measure the pH first. There was only a one strong base which was #66, so it was 1 M sodium hydroxide. And then there were two very strong acids, one of them didn’t show any visible reaction which is #65, so it was 1 M nitric acid, which means #60 was 1 M hydrochloric acid. #61 was a strong acid that didn’t react with any of the other solutions, so it was 3 M acetic acid; which means #68 was 0.1 M aluminum nitrate. #62 was a weak acid that did react with NaOH forming brown precipitate, so it was 0.1 M silver nitrate. Both of #63 and #69 are weak acids, but, #63 did react with 0.1 M silver nitrate, so it was #63 is 0.1 M zinc chloride, which means #69 is 0.1 M lead nitrate. #67 did react with 0.1 M silver nitrate, where #64 did not. In addition, #67 formed white precipitate with 0.1 M lead nitrate, so #67 was 0.1 M sodium chloride. So the #64 was the only weak base left which means it was 3 M ammonium