lovely sara عضو مميز
رقم العضوية : 192
الجنس :
نقاط التميز : 202
عدد المساهمات : 168 تاريخ التسجيل : 26/03/2010 العمر : 31
| موضوع: THE THIRD PROJECT OF ENGLISH الإثنين فبراير 21, 2011 9:42 pm | |
| the first experiment
Make a Battery from Potato
Introduction:
Batteries generate electricity through a chemical reaction between two different electrodes and one electrolyte. Use of Copper and Zinc electrodes and Sulfuric acid as electrolyte is a proven method for this process. We are wondering if we can use any other liquid as electrolyte? This gave us the idea of using a potato as electrolyte. After all a fresh potato has a lot of juice that may serve our purpose as electrolyte.
Problem:
Can Potato be used to generate electricity?
Hypothesis:
Potato juice contains many water soluble chemicals that may cause a chemical reaction with one or both of our electrodes. So we may get some electricity from that.
Material:
For this experiment we use: A fresh potato Copper Electrode Zinc Electrode A Digital or Analog Multimeter to measure Voltage or Current of produced electricity. Alligator clips/ Leads
Procedure:
We insert copper and zinc electrodes in to the potato, close but not touching each other. We use Clip leads to connect our electrodes to the Multimeter to measure voltage between two electrodes or current passing through the multimeter. For this experiment we removed the ****l of a broken AA battery for our Zinc electrode. (Make sure to test your multimeter by connecting its Positive and Negative wires to each other that should show no current and no voltage).
Record And Analyze Data:
A digital multimeter showed 1.2 volts between the electrodes, but the analog multimeter showed a much smaller value. In other words even though the voltage between electrodes is 1.2 Volts, the speed of production of electricity is not high enough for an analog multimeter to show the exact voltage. (Analog multimeter gets its power from our potato to show the voltage, but digital Multimeter gets its power from an internal battery and does not consume any of the electricity produced by our potato, that is why it shows a larger and more accurate value). We repeated this experiment with some other fruits and all resulted almost the same. In all cases the produced voltage is between 1 and 1.5 volts, and in all cases they do not produce enough current to turn on a small light. Another thing that we learned from this experiment is that creating electricity and making a battery is easy, the main challenge is producing a battery that can continue to produce larger amount of electricity for larger amount of time. By connecting multiple potato batteries you can make enough electricity to light-up a super bright light emitting diode (Included in the kit).
the second experiment Detection of nicotine in the smoke The experience How we can search about existence of the Nicotine in cigarettes: The Instruments: Ø Plastic Bottle Ø Cotton Ø Cigarette Ø Sulfur The Hypotheses We can do that by a simple experience and by using that simple Instruments The experience We close the head of the bottle by the cotton then we burn the cigarette in the head of the bottle (WP the cotton), then we press the bottle in order to bun the cigarette; here we observe that the cotton is colored by ye how color that substance is called «Nicotine».
The Final Results 1- When we bean one cigarette cotton’s color changes to ye how. 2- The cigarettes are very dangerous for the health of mankind because it contain poison «Nicotine». THE THIRD EXPERIMENT The process of photosynthesis prove the presence of starch in the green plants Introduction Plants are considered one of the most important factors to maintain the environmental balance and we can be aware of this fact through a simple comparison Experiment requirements; -plant of giranyum(green color) -a light source -black cover -three basins the first basin :boiling water the second: basin alcohol the third basin :water iodine -the source of heat -hour electronic -plate glass Prepare samples; we take the giranyum and put it in a pot three leaves from the plant the first leaf;completely exposed to light the second leaf;completely covered with black cloth the third leaf;partially covered with black cloth Experience step 1-the three leaves are then put in the first basin of water boiling 2-then the leaves are transported to the second basin of alcohol and let them for 10 minutes 3-then we put them in the third basin of water iodine for half an hour 4-get out of the basin the three leaves and clean them with water Note the results of the experiment: After cleaning the leaves with water we put them over the glass and we observe them,we note: 1-the emergence of blue-purple spots on the surface of the first leaf which was completely exposed to light 2-the emergence of non-blue-purple spots on the surface of the second leaf which was completely covered with black cloth 3-the emergence of blue-purple on half of the leaf exposed to light and doed not appear in the other half which was covered with black cover Conclusion of the experiment: Through the results we can say that the plant at light can install its own organic materials such as starch this process called photosynthesis and requires the presence of chlorophyll,light,carbon dioxide(co2),water and mineral salts [Conclusion: []Through this scientific experiment we know that the process of photosynthesis is one of the most important biological process on the surface of the globe this process needs all the necessary condition provided in the external and internal environment of the plant so that the process of photosynthesis occurs
عدل سابقا من قبل SISI ANGEL في الخميس مارس 17, 2011 6:55 pm عدل 3 مرات (السبب : اضافة تجربة) | |
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