Halide Ions Lab
Reactivity of Halide Ions
PURPOSE
The purpose of this experiment is to observe the reactions of halide ions with different reagents by mixing them together.
Materials
0.1 M AgNO3
0.1 M NaCl
0.1 M NaF
0.2 M KBr
0.2 M Na2S2O3
3% Starch Solution
4.0 M NH3 (aq)
5% NaClO (commercial bleach)
24 – well microplate thin – stemmed pipettes, 12
Safety
DATA
|PARTS |INITIAL MASS |FINAL MASS |CHANGE IN MASS |
| | | | |
|1 |119.9g |118.6g |1.4g |
| …show more content…
| | | |
|2 |162.7g |162.6g |0.1g |
| | | | |
THEORY/PRINCIPLE
The law of conservation of mass states that matter is neither created nor destroyed during a chemical reaction and that the mass of a system should therefore remain constant during any chemical process.
EXPERIMENTAL
The procedures for this experiment were simple enough to setup and follow. There were some confusion at first but as we read the manual it become clearer every time. The procedure is exactly in the manual.
CALCULATIONS
Vinegars mass (g)* + Baking soda’s mass (g)= Initial Mass
Initial Mass – Final Mass= Change in Mass
% error= | actual – theoretical | x 100 actual
*The vinegars mass (50 mL) includes the mass of the beaker which is 68g.
CONCLUSION/DISCUSSION
In this lab we learned that the law of conservation of mass only works when the reactants are enclosed. An example to this is in Part 2 experiment when we enclosed the reactants in a zip lock bag, which conserved the gas. With this we were able to get an accurate measure of both masses combined.
QUESTIONS
1. Describe all evidence indicating that a chemical change occurred in this experiment.
A chemical change occurred in this experiment when vinegar made contact with the baking soda making a bubbling and foaming effect, which indicates a reaction has occurred. After sometime the foaming has decreased and stopped.
2. Was the law of conservation of mass really violated in Part 1 as it appeared? Explain your answer.
The law of conservation of mass was indeed violated in Part 1. The initial mass was 119.9g, while the final mass was 118.6g making a difference of 1.4g. The reason for this is because the gases from the experiment were released out in the open, which means the mass would not be conserved.
3. Explain why the results for Part 2 were different from those in Part 1. What is the system in Part 1? What is the system in Part 2? How are they different?
The results for Part 2 were different from those in Part 1 because the plastic zip lock bag conserved the mass of the vinegar and baking soda in Part 2.
The system in part 1 was to “pour the vinegar into the beaker that contains the baking soda”. The system in part 2 was to pour the vinegar in the plastic zip lock bag that contains the baking soda and then lock up the bag. The difference between the two is that in part 1 the experiment is out in the open, while the experiment for part 2 is enclosed in the plastic bag.
4. How can this lab be used to prepare the Fun Science exhibits? Explain your proposal for packaging the contents, and write instructions for the participants who will visit the exhibit.
To prepare this lab for the Fun Science exhibits the two household substances must be in sealed containers, one container for baking soda with 4.0g, and one container for the vinegar with 100 mL. There would be two extra containers, one for the first experiment, and the second one would be the measuring container for the vin and a plastic zip lock bag for the second experiment. A single –pan balance would also be necessary to measure the mass. A data table with the labels already in the boxes would also be necessary. Also a weighing cup would be needed to measure the mass of the baking soda.
Instructions: Part 1 1.) Measure the mass of the container, then place 2.0g of baking soda in
the container. 2.) Measure the vinegars (50 mL) mass, once the vinegars mass was measured add both the vinegars and baking sodas mass and place the result in the table under the Initial Mass. 3.) Place the container, containing baking soda, on the balance and carefully pour the vinegar. 4.) Once the reaction has finished, measure the mass and record it under the Final Mass. Now calculate the change in mass. Part 2 1.) Follow the procedure of steps 1 and 2, but instead of using the container use the plastic zip lock bag. 2.) Once the both mass were record and placed under the Initial Mass, place the zip lock bag, containing the baking soda, on the balance. Then carefully pour the vinegar in the bag and then zip it up. 3.) Once the reaction has finished, record the mass and place the result under the Final Mass. Next calculate the change in mass.
5. Explain how the steps in the scientific method were used in this procedure.
The first step is to indentifying the problem, which is containing the gas to measure its mass. The next step is to perform the experiment and record the data.
PURPOSE
The purpose of this experiment is to observe the reactions of halide ions with different reagents by mixing them together.
Materials
0.1 M AgNO3
0.1 M NaCl
0.1 M NaF
0.2 M KBr
0.2 M Na2S2O3
3% Starch Solution
4.0 M NH3 (aq)
5% NaClO (commercial bleach)
24 – well microplate thin – stemmed pipettes, 12
Safety
DATA
|PARTS |INITIAL MASS |FINAL MASS |CHANGE IN MASS |
| | | | |
|1 |119.9g |118.6g |1.4g |
| …show more content…
| | | |
|2 |162.7g |162.6g |0.1g |
| | | | |
THEORY/PRINCIPLE
The law of conservation of mass states that matter is neither created nor destroyed during a chemical reaction and that the mass of a system should therefore remain constant during any chemical process.
EXPERIMENTAL
The procedures for this experiment were simple enough to setup and follow. There were some confusion at first but as we read the manual it become clearer every time. The procedure is exactly in the manual.
CALCULATIONS
Vinegars mass (g)* + Baking soda’s mass (g)= Initial Mass
Initial Mass – Final Mass= Change in Mass
% error= | actual – theoretical | x 100 actual
*The vinegars mass (50 mL) includes the mass of the beaker which is 68g.
CONCLUSION/DISCUSSION
In this lab we learned that the law of conservation of mass only works when the reactants are enclosed. An example to this is in Part 2 experiment when we enclosed the reactants in a zip lock bag, which conserved the gas. With this we were able to get an accurate measure of both masses combined.
QUESTIONS
1. Describe all evidence indicating that a chemical change occurred in this experiment.
A chemical change occurred in this experiment when vinegar made contact with the baking soda making a bubbling and foaming effect, which indicates a reaction has occurred. After sometime the foaming has decreased and stopped.
2. Was the law of conservation of mass really violated in Part 1 as it appeared? Explain your answer.
The law of conservation of mass was indeed violated in Part 1. The initial mass was 119.9g, while the final mass was 118.6g making a difference of 1.4g. The reason for this is because the gases from the experiment were released out in the open, which means the mass would not be conserved.
3. Explain why the results for Part 2 were different from those in Part 1. What is the system in Part 1? What is the system in Part 2? How are they different?
The results for Part 2 were different from those in Part 1 because the plastic zip lock bag conserved the mass of the vinegar and baking soda in Part 2.
The system in part 1 was to “pour the vinegar into the beaker that contains the baking soda”. The system in part 2 was to pour the vinegar in the plastic zip lock bag that contains the baking soda and then lock up the bag. The difference between the two is that in part 1 the experiment is out in the open, while the experiment for part 2 is enclosed in the plastic bag.
4. How can this lab be used to prepare the Fun Science exhibits? Explain your proposal for packaging the contents, and write instructions for the participants who will visit the exhibit.
To prepare this lab for the Fun Science exhibits the two household substances must be in sealed containers, one container for baking soda with 4.0g, and one container for the vinegar with 100 mL. There would be two extra containers, one for the first experiment, and the second one would be the measuring container for the vin and a plastic zip lock bag for the second experiment. A single –pan balance would also be necessary to measure the mass. A data table with the labels already in the boxes would also be necessary. Also a weighing cup would be needed to measure the mass of the baking soda.
Instructions: Part 1 1.) Measure the mass of the container, then place 2.0g of baking soda in
the container. 2.) Measure the vinegars (50 mL) mass, once the vinegars mass was measured add both the vinegars and baking sodas mass and place the result in the table under the Initial Mass. 3.) Place the container, containing baking soda, on the balance and carefully pour the vinegar. 4.) Once the reaction has finished, measure the mass and record it under the Final Mass. Now calculate the change in mass. Part 2 1.) Follow the procedure of steps 1 and 2, but instead of using the container use the plastic zip lock bag. 2.) Once the both mass were record and placed under the Initial Mass, place the zip lock bag, containing the baking soda, on the balance. Then carefully pour the vinegar in the bag and then zip it up. 3.) Once the reaction has finished, record the mass and place the result under the Final Mass. Next calculate the change in mass.
5. Explain how the steps in the scientific method were used in this procedure.
The first step is to indentifying the problem, which is containing the gas to measure its mass. The next step is to perform the experiment and record the data.