Lab 10 Solution Mystery

2. Write a statement to explain the molecular composition of the unknown solution based on the results obtained during testing with the Biuret solution and each sample solution.

The hypothesis is correct. Potassium chloride mixed with silver nitrate creates a white precipitate. Barium

concentration was plotted in order to estimate the concentration of the unknown solution (Figure 3).

Solub. Or Reaction w/ hot H20: no change observed from the cool water and is soluble

weak bases). After ranking the pH of these solutions, you will then test your predictions in the laboratory.

Day 1. Michael was coming home for vacation from college. When he got home he found out that

Substances A and B have an appearance of a white solid like. Substances A and B were put into a test tube and on the Bunsen burner. As a result, B melted faster than A. A was slow to melt. The reason why B melted faster than A is because it has a lower boiling point than substance A which made it melt faster. It also shows that A needs more energy than B to be broken down.

A 300.0-mL saturated solution of copper(II) peroidate (Cu(IO4)2) contains 0.38 grams of dissolved salt. Determine the Ksp.

Obtain a scintillation vial and label it using tape and a pen. For this part of the lab, make sure to record the mass of the empty vial using a digital scale before proceeding. Now, obtain 0.100 g of the same unknown substance and place into the vial. Record the exact mass again and be sure to take note of any crystal formation that occurs.

3.6.1. BAP (Benzyl amino purine) stock solution (2mg/ml): 20mg of BAP being weighed and dissolved completely in 1N NaOH to a final total volume of 10 ml with autoclaved double distilled water to obtain a stock concentration of 2mg/ml was prepared and stored in clean autoclaved vials at -4°C.

Unknown 12 was proved to be Proteus vulgaris. This organism was a gram-negative rod growing in single. This organism, which grew on a TSA plate, was catalase positive. A drop of H2O2 was added on to the colony and it began to bubble. Therefore, the catalase enzyme was present and broke down the peroxides in to non-toxic forms H2O and O2.

In experiment 3.11, we found out whether or not a larger amount of a liquid would get hotter when it boils. To answer this, we heated a specific amount of unknown liquid and recorded the temperature every fifteen seconds. In our scatter plot, we were able to find the boiling point of our liquid. We know that the slope of our graphs is when the liquid molecules were moving around and heating up. The plateau of our graph points is where the liquid started to evaporate and boil. This is were we found our boiling point at. Shantel and I decided that our boiling point was about 98º Celsius. If you had another slope in your graph, that was when you were simply heating the leftover gas. The histogram showed us that there were about equal amounts of data in the higher temperature (about 95º Celsius) bins for both 20mL of liquid and 10mL of liquid. Also, in the lower temperature bins (75º to 80º Celsius) there was about equal amount of data for 20mL of liquid and 10mL of liquid. There was 7 pieces of data for 10mL of liquid in the lower bins, and 6 pieces of data for 20mL of liquid. If a larger amount of liquid did have a higher boiling point, the clusters would be organized by volumes or amount. For example, all of the 20mL pieces of data would be in the higher temperature bins, and all of the 10mL pieces of data would be in the lower temperature bins or flipped. Rather, the bins were clustered by identity. The boiling point is a characteristic property.

For the concentration experiment three different concentrations were made of the KMnO4. Three test tubes were filled with 4 ml of water. The first test tube had 1 ml of the 500 KmnO4 added to it. Then the second test tube had 1 ml from test tube one and 4 mL of water. For test tube 3, 1ml was taken from test tube two. Each concentration was placed into a dialysis tubing using the strings to tie off one end and the clamp to close off the other end. Before the dialysis tubing was placed in the beaker, 1ml of a sample was placed in a cuvette to blank the spectrophometer. Each stir plate was set on a low speed and the dialysis was hung in the water by a string. Every 5 minutes that passed a sample of 1 ml was taken and put into a cuvette. The cuvettes were placed in the spectrophometer to measure the absorbance of each solution. The measuremnts were then recorded in lab notebook. Once the measurements were documented, the average of absorbance and concentration was recorded.

Copper starts to dissolve and bubbling occurs when nitric acid was added. The solution became green and the beaker started to become orange/brown as gas was being released. Solution then became light blue when washed with water.

The main objective of this experiment is to carry out qualitative analysis to identify metal cations in unknown solution 1.