Sabrina Hill.
Purpose: To better understand chemical reactions.
6.6
Mass a dry crucible and add about 1 gram of copper dust.
Find total total mass of copper and crucible.
Heat copper as shown in figure 6.5 for a total of two minutes.
While heating watch copper carefully.
When the crucible is cool mass the crucible and it's contents.
Record data and observations.
Reheat again for 15 minutes.
When the crucible is cool mass the crucible and it's contents.
Record data and observations.
Data
Mass of copper dust (grams) 1.03
Mass of copper after 2 min heat (grams) 1.03
Change in mass 0.00
Mass of copper after 15 min heat (grams) 1.03
Change in mass 0.00
Observations.
Turned silvery after a bout one minute.
Started to turn black.
At about six min it turns a charcoal color.
6.7
Add about 5cm³ of hydrochloric acid to the Copper Oxide.
Stir for 5-10 min.
Pour liquid in other test tube.
Wash remaining liquid.
• What does the remaining liquid look like?
It looks like water with blue or green dye in it.
• Is the black substance a mixture?
6.9
Set up as in figure 6.6.
Put a piece of zinc in the hydrochloric acid.
Stir from time to time rinsing after each use.
After zinc finishes reacting, pour off remaining liquid.
Wash zinc several times with water to clean off the acid.
Pour dry solid onto a paper towel and dry it quickly by pressing it between two more paper towels.
Press a scoopful firmly against the paper towel and across the dry solid.
Observations
The zinc starts to bubble at contact.
Zinc starts to turn dark.
Zinc starts to deteriorate.
It's bubbling furiously.
Looks black and rubbery.
Everything is all black dust.
One big piece of zinc is still partially intact.
Conclusion/ R.A.E questions
14. If you make a solution of salt and water , over watt range if values can you vary the mass ratio of salt and water to a given temperature?
15. a. Do you think gasoline is a single compound? See table 5.1 (pg. 93)
b. Would you except gasoline form different pumps to be the same? Why?
16. What would happen if you heated the solid that you recovered in this experiment?
17.How do you expect the total mass of solid that you recovered in experiment 6.7 and 6.9 to compare with the initial mass of copper you heated in experiments 6.7 and 6.9 to compare with the initial mass of copper you heated in Experiment 6.6?
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Whoever would like to add in these answers, I WOULD LOVE YOU FOREVER. Or give you chocolate.
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