Luena Bettencourt
9.2
HOW
DOES COPPER SULFATE AFFECTS THE
CURRENT OF 40 ML DISTILLED WATER?
RESEARCH QUESTION:
HOW DOES THE MASS OF COPPER SULFATE ADDED TO A 40 ML OF
DISTELLIED WATER AFFECT THE CURRENT OF IT? IT WILL BE ADDED FIVE
DIFFERENT MASS WEIGHTS EACH TIME .
HYPOTHESIS:
o The more mass of copper sulfate, that we mix with 40 ml of distilled water the
more current we have. I say this because the ions on the copper sulfate when
dissolving, the ions in it dissolve and get involved with the distilled water, the
more ions (copper sulfate) e put the more current we have.
VARIABLES:
The independent variable is the mass of copper sulfate that will be measured by weight
boat and the electronic scale.
The dependent variable is the current and is measured by the power pack and the
ammeter
My three controlled variables are: the volt number that is set in the power pack, the
quantity of water in the beaker and the quantity of the copper sulfate. The volt
number should stay always in the same place, in my case I start measuring the current
with 9 volt, so I shouldn’t increase or decrease, if I do that then the current will do be the
same, it could increase (if we increase the volt) or could decrease (if we decrease the
volt). My second controlled variable is the quantity of water that we put in, they should
be controlled because if we put more than it should be the current is not going to be the
same, I will make sure I control it by measuring well with the graduated cylinder. And
finally the last controlled variable is the quantity of copper sulfate that we add to the
40ml distilled water, it has to be controlled because once more, can change the current
and then we don’t get an accuracy work, a good way to control it is when measuring the
mass of cupper sulfate n the electronic scale.
Luena Bettencourt
9.2
METHOD:
Materials can be found at appendix A, at the end of the report.
1. Get all the necessary materials
2. Start by organizing your 5 beakers in a straight line and connecting and plugging
the power pack to the ammeter and the ammeter to the conductivity probe
3. With the graduated cylinder measure 40 ml of distilled water and put into one of
the five beakers.
4. Get the weight boat and put on top of the electronic scale, you will see that you
would get the weight of the boat (that’s fine), without taking the weight boat off,
click on the power bottom until it becomes 0.
5. When you have the electronic scale at 0 start filling with copper sulfate the
weight boat until it gets to 1g.
6. Now you have your 1g of copper sulfate, take the weight boat off and carefully
put into your beaker that was filled with 40 ml of distilled water.
7. After putting the copper sulfate in mix it up with a spatula or similar until the
copper sulfate gets dissolved.
8. Its time to measure the current. Turn on the power pack that should be already
connected with the ammeter and it with the conductivity probe and put the
conductivity probe into the mixed solution.
9. When you put conductivity probe into the solution try to see the first number
that you appears in the ammeter.
10. Take the conductivity probe out and record the first number that you saw in the
ammeter.
11. Put the conductivity probe again into the same solution and record the first
number that appears on the ammeter and record
12. Put one last time the conductivity probe in and repeat step 11 once more.
13. Repeat everything again from step 3 to 11, but now with 2 grams of salt.
14. Repeat everything again from step 3 to 11, but now with 3 grams of salt.
15. Repeat everything again from step 3 to 11, but now with 4 grams of salt.
16. Repeat one last time from step 3 to 11, but now with 5 grams of salt.
17. When you finish recording everything, calculate the average of the trials.
18. When you finish doing 5 times, (each time 3 trials) your data should be
something like this:
Your table should look like this.
Luena Bettencourt
9.2
When you finish mixing
your 5 solutions it should
look like this.
ANALYSIS:
TABLE:
Number of current in A when mass of cupper sulfate is added from 1 to 5 grams.
CURRENT A
Mass of cupper Trial 1
sulfate (g)
1
0.055
2
0.093
3
0.125
4
0.159
5
0.178
Trial 2
Trail 3
Average
0.053
0.074
0.130
0.154
0.180
0.030
0.092
0.119
0.162
0.192
0.046
0.086
0.124
0.158
0.183
Table: this table is showing the final numbers and averages of current in A when one to 5
grams of copper sulfate was added into 40 ml distilled water in a 200 ml beaker. The
current was measured using the ammeter and power pack, the copper sulfate with
electronic scale and finally the distilled water with the graduated cylinder.
FIND AVERAGE:
𝑠𝑢𝑚 𝑜𝑓 𝑡𝑟𝑖𝑎𝑙𝑠
Average=𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑟𝑖𝑎𝑙𝑠
0.55+0.053+0.030
Average=
3
Average= 0.046
The three trials for each mass of copper sulfate vary in the amount of mass added; the
numbers in my opinion are kind of reasonable for the number of mass that we put in.
Luena Bettencourt
9.2
But I can say that they are big numbers (big amount of current). I think my data has
concrete results that make sense with the amount of mass that were put in.
GRAPH:
How much the curent increases
every time is 1g is added?
Current (A)
0.2
0.15
0.1
y = 0.0342x + 0.0174
0.05
0
0
1
2
3
4
mass of cupper sulfate (g)
5
6
Graph: this graph is showing how the mass of copper sulfate added in the 40 ml of
distilled water can affect the current of it.
This graphs shows us how the current increases every time we add cupper sulfate. It
shows us a straight diagonal line, which helps us to understand better the increasing of
the current. The 0.0342 there is the slope that tells us the number of how much the
current increases every time we add a 1g of copper sulfate. The “y” interprets the current
and the 0.0174 that means if we didn’t put any copper sulfate in it would be 0.0174 A
that if we round it would be fortunately 0. This means that my data had an accurate
result.
EVALUATION:
Based on the data that I collected the independent and the dependent variables were
related because every time I added more copper sulfate (independent variable) into 40 ml
of distilled water, the current (dependent variable) would also increase. This agree with
scientific theory because the copper sulfate has ions that everytime they are added to
distilled water, increase the current because when the connectivity probe is placed in the
solution and connected to the ammeter the positive ions move to the negative terminal
and the negative ions move to the positive terminal. My hypothesis was correct. “The
more mass of copper sulfate, that we mix with 40 ml of distilled water the more current
we have. I say this because the ions on the copper sulfate when dissolving, the ions in it
Luena Bettencourt
9.2
dissolve and get involved with the distilled water, the more ions (copper sulfate) we put
the more current we have.”, this is actually what happened because the copper sulfate has
ions that when it gets to the water the ions separate and remain in the water.
My strengths during this investigation I think that was the amount of copper sulfate
choice that I’ve had made. The choice that I made of every gram having 1 gram of
difference can make more understandable I think for the people that are studying this
unit like my classmates and me because we can then see what a little gram of difference
can make, to change a simple current. I think my weakness was during the experience
that I wasn’t concentrated enough to see where the volt arrow is pointing at (in the
power pack), when recording my data, my results were very low because my volts
number were at 3 volts, so that made a lot of difference. Because our data wasn´t rigt we
had to do every thing over again, and that took us lot of time to actually work in this
report. Next time I do a similar experience I will make sure that the volts are in the right
place, before I start the experience.
APPENDIX
A:
Materials:
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5 beakers 200ml
1 graduated cylinder 100 ml
Power pack in the 9 volts
Electronic scale
Ammeter
Weight boat
Distilled water
Copper sulfate
Conductivity probe