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IPC Notebook
Contents Hard Rock Lab ................................................................................................................................ 2 Rock Reading .................................................................................................................................. 4 10+10=? Lab ................................................................................................................................... 5 Evaporation Lab .............................................................................................................................. 7 Napalm Lab ..................................................................................................................................... 9 H2 Demo (Explosion Demo) ......................................................................................................... 11 Copper Sulfate Lab ........................................................................................................................ 12 Electrolysis Demo ......................................................................................................................... 13 Penny Demo .................................................................................................................................. 14 Mythbusters: James Bond Special 2 .............................................................................................. 15 Firecracker Demo .......................................................................................................................... 16 Family IA Demo ............................................................................................................................ 17 Family IIA Element Lab................................................................................................................ 19 Flame Test Lab .............................................................................................................................. 21 Rates of Reaction Lab ................................................................................................................... 23
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Hard Rock Lab Purpose: To identify various rocks by their physical properties. Materials: Rock samples, streak plate, nails, pennies, glass slides Procedures: 1. Take a rock sample and scratch it with fingernail, penny nail, or glass 2. Record its color, luster and texture 3. Rub rock on streak plate and record its color 4. Identify each sample Results: Name
Letter Color Pinkish A Orange B Clear
Fingernail Penny
Nail Glass
Luster
Texture
Streak
O O
O O
O X
O X
Dull Glassy
Rough Smooth
Black Clear
Silvery-Black Turquoise
O O
O O
O X
O X
Shiny Glassy
Black White
F
Black
O
X
X
X
Dull
Rough Rigid Waxy Smooth
I J K L P Q
Black Clear Yellow Black & Gray Pink Maroon
O X O X O X
O X X X O X
O X X X X X
O X X X X X
Sparkly Shiny Dull Dull Shiny Dull
Smooth Smooth Waxy Smooth Rough Rough
Black Clear Yellow White Clear Brown
Feldspar Calcite Magnetite Galena C Fluorite E Graphite Galena Magnetite Gypsum Sulfur Talc Quartz Hematite
Black
Conclusion: In this lab we proved that a fast and easy way to identify rocks, by their physical properties, works very well. This method has big physical applications when geologists are in the field. All a geologist needs to identify a rock is a fingernail, a penny, a nail, a glass slide, a scratch plate, and a book. This seems like a lot, but everything except for the book is small enough to fit in your pocket. The tests are very easy and quick to perform. Each rock takes only about a minute to test. The results are pretty accurate because there is not very much to mess up on. On the scratch test, sometimes it is hard to tell if the nail scratched the rock or just if some rust
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rubbed off. This could be solved by using a new, clean nail. Also, there are inconsistencies between how hard the glass is. It seemed that the glass and nail had almost the same hardness. For results where very accurate results are necessary, the glass would need to be tested to make sure it is 5.5 on Mohs hardness scale. Our results were fairly accurate. We mixed up magnetite and galena which makes sense because they are both very similar. They both are a shiny black color. For some reason, our results said that galena was harder than glass (5.5); however its actual hardness is only about 2.7 on Mohs hardness scale. There are a few ways that this mix-up could have happened. One way is that a transcribing/data transfer error was made and galena went from being softer than everything to harder than everything. Another error that could have happened is that because galena is so shiny and dark, it may have been hard to see the scratch marks that were made on the rock, so we assumed there were none. I’m not too sure which one of these it was, but we did make an error.
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Rock Reading Minerals are the building blocks of the Earth’s crust. To be officially classified as a mineral they must be inorganic (never was alive), naturally occurring, a solid, and it must have a definite chemical composition. Most minerals also have a crystal structure that repeats, but it is not necessary for it to a mineral. Some minerals can be identified by their color; however, color can be very deceiving if that is all you go by. For example, real gold, pyrite (fool’s gold), and chalcopyrite all have very similar golden colors, but they are all very different. On the other hand, malachite and is very green. No other rock is quite like it in color, so color is the only property you need to determine that it is malachite. Having a rock like that is a very rare occasion. To identify most rocks, you need all the other properties. These are: hardness, streak, luster, density, crystal systems, cleavage, fracture angle, and special properties like fluorescence, radioactivity, reactivity and electrical properties. With these properties, you can identify almost any rock.
This is malachite. Notice its green color.
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10+10=? Lab Purpose: To determine if a physical or chemical change takes place. Materials: Two graduated cylinders, ethanol, and water 1. Procedures: 2. Add 10mL of Ethanol to 1 graduated cylinder. 3. Add 10mL of Water to the other graduated cylinder. 4. Mix and observe. Observations: Bubbles are coming out of the bottom. Total volume is 19mL! Murkiness on top.
The left box is two alcohol molecules. The right box is alcohol mixed with water. The left box has a “density” of 3.6 atoms per in². The right picture has a “density” of 8.73 atoms per in², over twice 3.6.
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Conclusion In math, 10+10 is always 20, but sometimes in science, it isn’t 20. When we mixed the water and the alcohol, the water molecules packed into the space between the alcohol molecules, which made it so that the solution only took up 19 mL instead of 20. Since no matter was destroyed because it wasn’t a nuclear reaction, it had to have been a chemical change, a physical change, or nothing happened. There were no signs of a chemical change like color change or change in temperature. There were no signs of physical change either. This means that the water molecules must have just slipped into the space between the alcohol molecules. Because the amount of matter in the graduated cylinder (the mass) did not change, the density must have gone up a little. By decreasing the amount of empty space, the total volume decreased. In our trial, the volume after mixing was a little over 19mL because we measured wrong when adding the alcohol. We were not at eye level when reading the volume, so we added about 11 mL instead of 10mL.
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Evaporation Lab Purpose: To see which liquid evaporates faster. Materials: Alcohol, Water, Small beakers, Hot plate, Stopwatch Procedure: 1. Pour 10mL of alcohol into a small beaker 2. Pour 10mL of water into an equally sized beaker 3. Place beakers on the hot plate 4. Start timer and observe
Observations 4:05
Water has bubbles on bottom
4:45
Vapor from water; alcohol still not boiling
5:50
Alcohol boils vigorously; water still steams
9:30
Alcohol almost gone
10:51
Alcohol all gone
11:45
Water vigorously boiling
18:26
Water still boiling Water
Alcohol
What our hot plate looked like 11 minutes into the experiment.
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Conclusion In this lab, we proved that alcohol boils faster than water. This is a very good fact to know because sometimes you need something that boils quickly and easily, to take away heat, for example. When anything evaporates, it takes heat with it. The higher the evaporation point, the more heat it takes to get it to get it to its evaporation point. Because alcohol’s evaporation point is over 21°C lower than water’s, it evaporates much more readily and faster. This is what makes it more practical to put a rag soaked in alcohol on a feverish person’s head than a rag soaked in water. The alcohol evaporates faster, which means that it takes the heat away faster. In our experiment, for some reason, the water started steaming first. Once the alcohol started to boil, it boiled like crazy. The bubbles were shooting up from the bottom of the beaker so fast that it looked like a whirlpool. Until we saw the speed and intensity with which the alcohol boiled, we thought water was going to boil first. Water didn’t start boiling with the same vigor that alcohol had been boiling with until almost a minute after all the alcohol had boiled away.
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Napalm Lab Purpose: To determine if a physical or chemical change takes place. Materials: Methanol, Calcium Acetate, Dish, Spoon, Matches Procedures: 1. Put one spoonful of calcium acetate in the dish 2. Saturate with Methanol 3. Put on table and light Observations: Burns for a long time No smoke Fire is blue then orange Mixture turns black where it was burned
In the picture on the left, the methanol is burning. On the right, the acetone is burning
Conclusion In this lab, 4 changes occurred. Three of them were chemical changes and one of them was a physical change. First, we mixed the calcium acetate and the methanol. This was a physical change because it made a mixture which is not a chemical change. Then, we lit the mixture on fire. Because the calcium acetate is not flammable, only the methanol burned. Burning is always a chemical reaction. The intense heat produced by the burning methanol broke the chemical bond in the calcium acetate. The calcium acetate broke into calcium and acetone. That was the second chemical reaction. The third chemical reaction occurred because the newly created acetone is flammable. The still
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burning methanol lit the acetate and the acetone began to burn. The reason the fire change from blue to orange is because the substance that was burning changed. Methanol burns with a bluish color that can be invisible in bright light and acetone burns with an orange, darker color.
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H2 Demo (Explosion Demo) Observations: HCl bubbles when we added Magnesium Magnesium is gone Heat Gas is being produced Explosion! Woosh noise
The HCl creating Hydrogen bubbles after the aluminum was added.
Conclusion
When we added Magnesium to the Hydrochloric acid, it produced Magnesium Chloride and pure hydrogen. This reaction is Mg + HCl → MgCl2 + H2. The reaction is exothermic which explains why we felt heat. We captured the hydrogen gas in our other test tube. The hydrogen all went into the upper test tube because hydrogen’s density is less than air’s. After we collected all the hydrogen, we lit it on fire. The hydrogen is very flammable and combined with the oxygen in the air to form water vapor. The woosh noise we heard was created because the air and other gasses in the test tube were moving and expanding very fast. The gas expanded because it got very hot very fast.
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Copper Sulfate Lab Purpose: To observe a single replacement reaction. Materials: Copper sulfate, zinc flakes, test tubes, test tube rack Procedures: 1. Put 2 mL on zinc flakes in the test tube 2. Add 5mL of CuSO4 to test tube 3. Observe for 30 min Observations: Warm Changed color
Zinc flakes in the copper sulfate
Conclusion In this lab, we performed a single replacement reaction. The zinc flakes reacted with the copper sulfate to make zinc sulfate and copper. The reaction in shorthand is CuSO4 + Zn → ZnSO4 + Cu. The copper and zinc switched places which made the reaction a single replacement reaction. Although we didn’t have the time to observe for 30 minutes, by shaking the test tube, we made the reaction happen faster, so it was as if we actually waited 30 minutes. As the copper sulfate changed into zinc sulfate, it change from blue to clear. This is because the aqueous copper sulfate is blue but the aqueous zinc sulfate is clear. Unfortunately, because we didn’t have enough time, we were not able to watch the copper change colors to red and blue.
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Electrolysis Demo Observations: Hydrogen made Pop! sound Oxygen made flame brighter then put it out Hydrogen and Oxygen made louder Pop Drawing:
The airflow that causes the noise that the fire produces.
Conclusion In this lab, we used electricity to split the water molecules into hydrogen molecules (H2) and oxygen molecules (O2). We then lit the Hydrogen on fire, which produced a Pop/whoosh noise. This noise is caused by rapid airflow in the small test tube. When we tried to burn the oxygen, it didn’t work, however, it did make the flame on the match a little brighter. The reason this happened is because fire needs oxygen to burn, and with more oxygen available to the flame, it can burn brighter. The fire went out very quickly because all the oxygen was used up and so there was no more available oxygen to the fire. Without oxygen, the fire stopped burning. When we combined both hydrogen and oxygen in the air, it made an even bigger explosion because there was more oxygen to sustain the fire for longer.
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Penny Demo Observations: Nitric Acid bubbles Penny and Nitric Acid turn green Brownish gas is produced Penny is thinner
Conclusion
In this experiment, we added a copper penny to nitric acid and observed the results. First, the liquid in the bottom of the beaker turned a greenish blue color. The liquid at the bottom (copper nitrate) began to produce a brownish gas (Nitrous oxide). The Nitrous oxide is a big component in pollution which is why in heavily polluted cities, the clouds look sort of brownish. The chemical formula of the reaction is: Cu(s) + 4HNO3(aq) ——> Cu(NO3)2(aq) + 2NO2(g) + 2H2O(l) At the end of this reaction, the penny was considerably cleaner and thinner than before. This was caused because some of the copper was eaten up by the reaction and turned into copper nitrate. When we poured water into the beaker, we diluted the copper nitrate so that when we poured it down the drain it would not react with the materials in the pipes which could cause pluming problems and safety problems.
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Mythbusters: James Bond Special 2 For this science documentary, I watched Mythbusters. The episode that I watched had three myths that were: cutting through a steel cable with steel teeth, an exploding pen, and a hat that decapitates statues. All of them were busted. In order to cut through a metal cable, you need something sharper than the metal teeth shown in the James Bond movie and more force than a human jaw can deliver. For a pen to make a big enough explosion to replicate what was in the movie, you would need a super jumbo sized pen. Someone might get suspicious if you handed them a pen that big. Even at superhuman speed and a direct hit, a hat with a sharpened steel rim could not cut through a solid marble statue. My favorite myth that they tested was the hat one because at one point they thought the myth was confirmed because they knocked the head off of the statue, but then they realized the statue was hollow.
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Firecracker Demo Observations: Lots of paper Paper is tightly wrapped Brownish powder on top, gray powder in middle Big boom when we lit the firecracker Not a very big boom when we lit the powder
Conclusion In this demo, we dissected a fire cracker and then burned the gunpowder that was inside. First, we had to take the paper wrap off the outsider of the firecracker. This lets the pressure inside the firecracker build so it makes a pop sound instead of just burning. The clay just stops up the ends so the gunpowder stays in. In addition to gunpowder, there is also sulfur and potassium nitrate. The sulfur makes a lot of gases when it burns which makes the firecracker explode. When the potassium nitrate gets hot, it splits into oxygen, nitrogen and potassium carbonate. The oxygen fuels the fire which makes more potassium nitrates split. This chain reaction produces a lot of hot gases very quickly which explodes the paper wrapper and makes the POP noise that firecrackers are known for.
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Family IA Demo Observations: Magnesium burned really bright- So bright you couldn’t stare at it. The Magnesium fire white white instead of the normal orange or blue. After Magnesium ribbon burned, it turned a whitish color. Potassium reacted violently with water It began to burn
A magnesium fire
This is some potassium (K)
Conclusion
In this demo we experimented with metals. First, we lit magnesium on fire. The magnesium was not very easy to burn, but when it did catch, it burned very bright. The light it put out was white and so intense, it hurt to look at. When the Mg burned, it released photons of different energies and wavelengths. This combination is what made the light white. Magnesium fires are good for places where they need to last because they can’t be put out by water or carbon dioxide. In fact, if you put water on a magnesium fire, it will make hydrogen which makes the fire bigger and can even cause an explosion. When we dropped the potassium (K) into water it reacted with the water. The reaction is: 2K(s) + 2H2O(l) → H2(g) + 2KOH(aq) . This reaction also produces a lot of heat. The heat produced by the reaction is actually enough to ignite the hydrogen gas. The
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Hydrogen gas burns and also, its production and burning propels the piece of potassium around.
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Family IIA Element Lab Purpose: To determine how reactive elements are in a family. Materials: Well plate, 7 chemicals Procedures: 1. Place 2 drops of each chemical into well plates according to the following chart. 2. Observe and record results. K2SO4
K2CO3
K2CrO4
Ba (NO3)2
1
1
1
Sr (NO3)2
2
2
2
Ca (NO3)2
3
3
3
Mg (NO3)2
4
4
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Well Plate Conclusion In this lab, we combined different chemicals to test their reactivity. What we found fit the periodic trends exactly. In Family IIA, the farther down you go, the more reactive the element. This was exactly what happened; the most reactive compound was the one with Barium (Ba) in it because barium has the highest atomic number and mass. The second most reactive was the compound with Strontium in it. This trend continued on with the magnesium compound being the least reactive of all of the compounds. Based on this trend, I can even predict that if we had the Radium nitrate, Ra (NO3)2, it would be more
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reactive than any of the others. Likewise, if we had Beryllium nitrate, Be (NO3)2, it would be less reactive than any of the compounds that we tested. The periodic table’s trends are very consistent throughout chemistry.
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Flame Test Lab Purpose: To determine the color which different chemicals burn. Materials: Bunsen burners, wood splints, metal salts Procedures: 1. Place splints in solution and then into flame 2. Record color of the flame 3. Repeat with the other solutions. Results
Conclusion
Chemical KCl CaCl2 CuCl2 NaCl SrCl2 LiCl BaCl2 Mg
Color Peach Dark Orange Bluish Green Orange Red Red Orange (Supposed to be green) White
A Barium Fire
A Potassium fire
In this lab, we lit different color salts on fire to see the different colors they produced. Our results were not completely accurate; Barium was supposed to be green not orange. This was a very cool lab. The different chemicals release different energy photons when they burn. This is what causes the color. Usually, when we think of fire, we think of red, orange, and yellow. As you can see in the pictures, not all fire is those colors. The magnesium strip, which released white light, releases photons of every different energies. The combination of photons of every color made the fire look white. The real- life
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applications on this are huge. These chemicals are used in fireworks to make the firework a different color. They are also used in flare to make the flares more noticeable.
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Rates of Reaction Lab Purpose: To determine the factors that affect the rates of a reaction. Materials: Well plates, Alka-seltzer, potatoes, Hydrogen peroxide, stop watch, beakers Procedures (a): 1. Place the potatoes in well plates according to the diagram below. 2. Add H2O2 until the wells are ½ full and observe for 30 minutes. ½
Full
¼
Procedures (b): 1. Break one alka-seltzer tablet into 4 equal parts 2. Place ¼ piece into hot water, and start the stopwatch 3. Wait until it is dissolved and stop the stopwatch 4. Repeat steps 2 and 3 using tap water and cold water 5. Crush the last piece, place it in tap water and start the stopwatch 6. Wait until it is dissolved and stop the stopwatch
Results Most Foam
Variable Hot Water Cold Water Tap Water Crushed in Tap water
2nd most foam
3rd most foam
Barley any foam
Time 0:11 2:10 0:57 0:37
Conclusion In this lab, we tested and proved all four ways to speed up a reaction. The first way, adding a catalyst, was tested in part A, where we added potato (a catalyst) to the
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hydrogen peroxide. This caused the reaction between the air and the H2O2 to happen a lot quicker. The amount of foam on the top of the well plate shows the speed of the reaction because the faster the reaction, the more foam will be made. Adding a catalyst made the reaction go much faster than if there was no catalyst, as you can see by comparing the amount of foam in the first 3 wells with the amount of foam in the 4th well plate. The second way to speed up a reaction, increasing the concentration, was shown also in part A, evidenced by the fact that as the amount of potato increased, the amount of foam produced also increased. The third and fourth ways to increase a reaction were proven in part B. When the temperature of the water increased, the speed at which the alka-seltzer tablet reacted with the water greatly increased. If decreased by over 1100%! Also, the third way to increase the speed of a reaction, improving surface area, was shown in part B. When we crushed the Alka-seltzer tablet, it decreased the time it took to dissolve because there are more places where the reaction can take place.