Part B: A similar experiment was performed after the 15% NaI in acetone solution. This time, ten test tubes were marked and we put 2 mL of 1% ethanolic silver nitrate in each test tube. The same corresponding halide was added to the mixtures as the first part of the experiment. Once these halides were added, we observed to see which turned cloudy. The mixtures that didn’t turn cloudy were put into a hot water bath of about 100 C for about a min.
Measure the solution by right clicking on the beaker and choose pH meter *Then I had to measure the pH of 0.1 M sodium hydroxide Get a 100 mL beaker from the equipment menu Right click on the beaker, select chemicals, and add 50 mL of 0.1 M sodium hydroxide. Measure the solution by right clicking on the beaker and choose pH meter Part 2: *First add 35 ml of unknown acid a to 100 mL beaker. Select all chemicals from the toolbar in the chemicals section, choose unknown acid a. Put the volume at 35 mL in a new 100 mL beaker. *Then add two drops of phenolphthalein indicator to the beaker by right clicking, choosing indications, and adding 2 drops of phenolphthalein.
Repeat steps 1-5 for trial 2. Variables and Control test: Independent Variable: Amount of each reactant poured into the test tubes Dependent Variable: Height of each solution Constant variables: Amount of time waiting for solution Data Table: Test tube # | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | Trial 1 | 0.5 cm | 1.0 cm | 1.1 cm | 1.5 cm | 1.5 cm | 1.5 cm | 1.3 cm | 1.5 cm | Trial 2 | 0.5 cm | 0.7 cm | 1.0 cm | 1.0 cm | 1.3 cm | 1.7 cm | 1.9 cm | 1.5 cm | Observation/Analysis: Solution turns yellow when a separate product is added, solid of the solution leaks down to the bottom after 20 minutes. Conclusion: The group tried to find the excess or limiting for the reaction between KI and Pb. In the end the hypothesis was supported by the data. We found that little amounts of each product led to a greater height of solids.
The mass was recorded and transferred to a 50 ml beaker. 4 ml of 6 M HNO3 was added to the beaker containing the copper. For step 2, 10 ml of distilled water was added to the beaker. Then, 6 M NaOH was added to the solution (drop wise), until placing a drop of the solution on red litmus paper turned it blue. For step 3, the solution was heated with a hot plate.
The buret had used the NaOH thoroughly rinsed three times because at the first titration the NaOH solution was used. About 50Ml the NaOH solution was in a clean beaker and brought it to experiment area. A funnel was used to fill the NaOH into the buret and recorded the initial volume on the buret to the correct number of significant figures. A pipette was used to take 10.00ml HCl into a clean 50mL Erlenmeyer flask. Three drops of phenolphthalein indicator was added into the HCl solution.
Once the buffer tablet has dissolved into the water, add 10 ml of starch solution. 3. After the starch solution has been added, add 10 ml of enzyme solution to the current solution, simultaneously start the timer and record at 1 minute intervals. 4. In addition, place iodine in the dropping tile in order to identify if starch is currently present.
The last sample prepared was at 25ᵒC. When mixing the solutions, the CaCl2 was slowly added to the NaCO3 at a rate of approximately 10mL/minute. The beaker was also simultaneously stirred as the CaCl2 was poured in. Once combined, a thermometer was used to measure and record the temperature. The mixture was then allowed to sit at temperature for 5 minutes.
To get accurate result, this titration process are repeated for another two times. The entire procedure by which we obtain the molarity of a solution of one substance (NaOH) from an accurately known amount of another substance (KHP) is called standardization. The average molarity of the sodium hydroxide solution will be used in the next experiment. The second experiment is conducted to determine the molarity of acetic acid and mass percent in vinegar. 100mL of distilled water was added to 10mL of vinegar and followed by 1mL of NaOH was pour into the solution.
By doing this, it will show the initial pH before any acid or base has been added into the solution. Followed by that, add 5 drops of .1 M HCl into the tube, mix, and record the new pH in the acid row found on Table 1. After that continue adding 5 drops at a time until 30 drops total have been added, make sure to record the pH in-between every 5 drops. Once 30 drops have been reached, quit adding and record the final pH. Using the other test tube of the same solution, again, measure the initial pH and repeat the same procedure except adding .1 M NaOH, followed by recording the data in the base row in