Hot Ice Lab

Recently in chemistry we were given the opportunity to split into groups, and go off and do our own experiments. My group decided we wanted to try and create hot ice. It’s a relatively simple lab to run. All you need is some water, sodium acetate, a fridge, and something to warm the water. You begin warming the water and adding sodium acetate to it. Stir the mixture, making sure every last bit is dissolved. KEEP ADDING sodium acetate until the water will no longer dissolve anymore. Heat the solution to near boiling temperature. Pour the solution through a filter, so there is no extra undissolved materials or this will not work.Then put it in the fridge, letting it cool for a bit. Now after a bit of cooling you have a solution to make statues and what not with.

This works because the solution is super saturated. It is able to go from near boiling and be super cooled to well below melting point without crystalizing, until it is given a base to crystalize on. The second the solution touches something, such as the oil from your finger, anything on the counter, or anything else, it begins to crystalize on the object. The substance looks like ice, but is actually just solid sodium acetate. The reaction is exothermic and thus gives of heat, giving it the name,”Hot Ice.”

 

Silver/copper replacement lab

In chemistry we got a 30cm piece of copper wire cleaned it off, coiled it, and put it in a test tube. Our coil weighed 3.443 grams. We poured .995 grams of silver nitrate into the test tube with the copper wire. Then we added distilled water up to 2 cm from the top of the test tube. We covered the test tube with parafilm, and waited a few days.

After waiting , we weighed a piece of filter paper to be 1.45 grams, and set it up with a funnel to separate the the silver. We removed the silver, copper, and waste from the tube. We got as much silver as we possibly could onto the filter paper, the waste in another beaker, and the copper coil we let dry on a paper towel. We let everything dry overnight. The next day we measured the copper to be 3.227 grams, and the filter paper/silver to be 2.175 grams. This means that .216 grams of copper reacted with the silver nitrate, and produced .455 grams of silver.

Evaporation and Intermolecular Attractions lab

In this experiment we studied the temperature changes caused by evaporation in 6 different liquids. We used 2 alkanes, heptane(C7H16) and hexane(C6H14). we also used four alcohols; methanol(CH3OH), 1-butanol(C4H9OH), 1-propanol(C3H7OH), and ethanol(C2H5OH). Our other materials were; Macintosh computer, Serial Box Interface, Data logger, 2 Vernier temperature probes, and rubber bands.

We recorded the beginning temperatures of each liquid, then allowed the to evaporate and recorded each temp until they no longer decreased in temp. After they we calculated the change for each.

After we recorded, my group(Sam, Joel and me), created the graph below displaying our results.

Ethanol, propanol, butanol, and methanol all have hydrogen bonds.

Baking Soda and Vinegar Reaction

We worked with some of the most well known reactants, baking soda and vinegar. The point of this reaction was to put the baking soda in a beaker, and slowly add vinegar until they stopped reacting. We were to measure how much of each was used, and figure out how many moles of vinegar reacted equally with moles of baking soda. Baking soda and vinegars chemical equation in this reaction are NaHCO3+HC2H3O2—>CO2+H2O+NaC2H3O2. We used 1 gram of baking soda in this reaction, and measured the amount of 1 mole of baking soda to be 84 grams. So we used .012 moles of baking soda in this reaction. We also used 10.5 grams of vinegar in this reaction, and measured 1 mole of vinegar to be about 60 grams. Of this mole of vinegar only 5% was the acetic acid that reacted with the baking soda. So we used .175 moles of vinegar, and .00875 of that was the acetic acid that reacted with the baking soda. This lab was really fun, and I would very much enjoy working with the same materials on a much larger scale.

Balance lab

Recently we worked with copper (II) chloride and aluminum. In this lab we were supposed to try and measure amounts of both, and try to get them to react evenly. In one trial we got very close. My group of Joel,Sam, and me put 20 grams of copper(II) chloride and around 3 grams of aluminum. Our trials ranged in color from bluish green, to pink, to black. The bluish green meant there was still copper(II)chloride, pink was the ideal color, and well black was fun. When the product was black, foam began rises, and the black liquid began to launch out the tube making a sort of nasty mini volcano.

My fun volcano:

http://www.youtube.com/watch?v=aP7GQQp5CaA&feature=youtube_gdata_player

Elements and Reactivity

Recently I became curious of which element was the most reactive, and I notice I had no points in my research standard for chemistry. I decided I could cure my curiosity and get points at the same time, and this is what I discovered.

 

Of the elements, group 1A is either the most or one of the most reactive groups of elements. These elements are known as the alkali metals. These metals are so reactive they are not found natural in nature. These elements are:

Lithium(Li)

Sodium(Na)

Potassium(K)

Rubidium(Rb)

Cesium (Cs)

Francium(Fr)

These elements only have 1 electron in their outer shell, and are more than willing to get rid of it through ionic bonding.

Another Competing group for most reactive are the Halogens. The Halogens are group 17 and  contain 7 electrons in their outer shells. These elements are also only found combined with other elements in nature.

Fluorine(F)

Chlorine(Cl)

Bromine(Br)

Iodine(I)

Astatine(At)

Of these groups of elements, Fluorine is most likely the most reactive. It can react with almost anything, and able to combine with things such as some glasses and some noble gasses. No chemical substance can free fluorine from it’s bond, which made it very difficult for scientists to isolate it.

 

These are some the things I’ve learned in my adventure for learning about very reactive elements, and of these i think fluorine takes the cake.

 

Sources:

http://www.chemicalelements.com/groups/alkali.html

http://en.wikipedia.org/wiki/Halogen

http://education.jlab.org/itselemental/ele009.html

 

Conductivity

In this lab we dissolved substances in water. We used battery testers to test if they were conductive, and how conductive each substance was. Although some were more conductive than others, some of the substances didn’t even show any conductivity. This was a fun lab, and I would very much enjoy testing many other substances for conductivity.

 

Reactions

This week in chemistry we have been working with reactions. We did seven different experiments, testing what different gases like Oxygen, Carbon DiOxide, and Hydrogen would do with a little fire. We used things like hydrochloric acid, copper, and magnesium. The experiments allowed us to control how fast we did the experiment, what we did, and pretty much we worked with almost no teacher guidance.We did seven different reactions.

1. We put a strip of Magnesium into a test tube filled with Hydrochloric acid. We used another test tube to hold the gas inside, lit a match, and made a sort of micro explosion. Chemical formula:2HCL+Mg–>H2+MgCl2
2. We burned magnesium until it began flashing an extremely bright light, gas floated off of it, and only white powder remained.2Mg+O2-heat->2MgO
3. For the third experiment we burned copper wire for seven minutes.                             2Cu+O2-heat->2CuO
4. For the fourth experiment we heated up ammonium carbonate.                            (NH4)2Co3-heat->2NH3+CO2+H2O
5. For the fifth we put hydrogen peroxide in a test tube, and added manganese dioxide. We lit a splint and blew it out leaving it glowing red. We put it in the test tube and it relit. 2H2O2-MnO2->O2+2H2O
6. For number 6 we poured some potassium iodide into a test tube, lead nitrate into another, and then in a third we mixed them.2KI+Pb(NO3)2–>2KNO3+PbI
7. For number seven we poured copper(II) carbonate into a test tube, and heated it. We used a second test tube in an inverted position to contain the gas. We lit a splint, put it in the test tube, and the fire went out. CuCo3-heat->CO2+CuO

Through these experiments we learned how the three gases hydrogen, oxygen, and carbon reacted with fire and other substances.

My Magnesium Lab

In science we have been working with ionic compounds. Recently we worked with magnesium ribbon. Our materials consisted of magnesium ribbon, a crucible, a ring stand and ring, clay triangle, crucible tongs, 100-mL beaker, conductivity tester, distilled water, laboratory burner, and a scale. We measured the mass of the magnesium, crucible, and the magnesium inside of the crucible. We then placed the crucible(magnesium inside) on the ring and began heating it. After about a minute the magnesium ignited, and we turned off the burner. Inside the crucible was a whit powder product. We poured this product in our beaker, and mixed it with distilled water. We checked it for conductivity, and it turned out to be conductive.

Light Spectrum

 

 

This week we’ve been working with, and learning about light spectrums. We learned about continuous, emission, and absorption spectrums. A continuous spectrum, is when a band of light from it’s source gives off the complete band of colors without any missing. An absorption spectrum is when a colder object such as a cloud or in our case a bottle of colored water is placed in front of the light source. The band of light you see through the spectroscope is disturbed. It absorbs some of the colors, and the color you see most is normally the color of it since it reflects this color. Emission, is the light bands a source gives off, depending on the source it may give of a full band of light or only a few colors of the band.

examples of what i saw(no order):

Hydrogen-Purple, turquoise, red

Mercury-Purple,green, orange, blue

Nitrogen-Purple, red, yellow, green, orange, blue

Argon-Red, purple, green, yellow

Helium-Red, yellow, purple, turquoise

Neon-Red, orange, yellow, green, blue, purple

 

 

This is through a cylindrical spectroscope

This was through our triangular spectroscope.