- Data tables (use graph paper)
Time (seconds)
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COLD ACID Volume (cm3)
video #2
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HOT ACID Volume (cm3)
Video #3
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05 |
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10 |
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15 |
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20 |
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25 |
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follow with the measurements until the reaction stops for AT LEAST one minute….. |
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- Graph
- Graph showing the time in the “X” and volume of water displaced by the gas on the “Y” (use graph paper).
- Use ONLY ONE GRAPH for both experiments. Mark the values for hot acid using red pen/pencil. Mark values of cold acid using a blue pen/ pencil
- Do not connect the dots, draw the line (curve) of best fit.
- Analysis questions
1) How are the graphs for the cold and hot acid similar?
2) How are the graphs for the cold and hot acid different?
3) In which condition you got more gas delivered? How you can explain this?
4) What can you infer from both experiments?
5) How would the graph look like if you use acid at 100 ºC? (sketch in a small piece of paper showing your hot and cold acid in red and blue and the prediction in black)
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6) How would the graph look like if you use acid at 0 ºC? (sketch in a small piece of paper showing your hot and cold acid in red and blue and the prediction in black)
7) How would the graph look like if you use 2.5 cm of Mg instead of the 5 cm? (sketch both graphs in one)
8) What would you expect to see if you use magnesium powder? Why?
9) What is the gas that was generated in the graduated cylinder? How can you prove it in the lab?
10) Write the balanced chemical equation for the reaction between HCl and Mg.
11) How many moles of HCl were present in the 50 mL of 1M solution?
12) 5 cm of magnesium have around 0.085 g of Mg metal. How many moles of Mg. were present in the sample?
13) Which is the limiting reactant in the reaction produced in the conical flask?
14) Assuming that at room temperature ONE MOLE of any gas occupies 24 L, which is the expected volume of the H2 gas produced in the reaction?
15) The amount of gas obtained during the lab is the actual yield. The amount of gas predicted in question #14 is the theoretical yield. With this information, which is the percent yield of the reaction?