The Hydrates Lab

Before I begin to talk about this experiment may I include that this crystal lab blew my mind! (CuSO4 5H2O) We got blue crystals that weighed 5 grams and put them in a test tube over a flame to heat them up. When they were over the burner they began to turn white because the water was evaporating from the crystals. After they were fully white we weighted them in a cup at 1.73, this means that 3.2 grams of water evaporated. We got distilled water and poured it in the white crystlas and BOOM they turned back to the same exaclty blue color they started with!!

The blue crystals(with water)

 The effects of it becoming white after heating it up

Silver/Copper Replacement Lab

We got a copper wire that was about 30 cm long and coiled it around a pencil forming a spring like structure. We placed the sprinted copper into a tube and made sure it reached from the top to the bottom. When it did, we set it aside for later use. . . We weighted some silver nitrate and it cam to 1.018 grams. We transferred the silver nitrate into the test tube and poured distilled water until the water was 2 centimeters from the top. Then we covered the top of the test tube with parafilm, and you place your thumb on top and shake until the silver nitrate was all dissolved. After that we took the stretchy parafilm off and observed the reaction it made, it set their all week because Mr. Ludwig said that it would take time for it to react. The very next Monday we came back to school and the craziest thing happened!

It looked so pretty i didn't want to mess it up but we had to in order to get to the next step. Nika shook the tube and poured the substance in a filter we made with paper that weighted .906 grams. We took the coiled copper out and placed it on the side on a paper towel it weight 3.17 grams. Then we let that sit for a day so it could filter out all the way out. The next day the silver was dry in the paper filter and we weighted it and it was 2.17 grams.

measurement and calculation

sample 1:
CuO-->   Cu= 1               Cu/ total> 100= 64/80= 80%Cu/20%O
                O= 1*16
sample 2:
Cu2O-->  2*64  128         128/144> 100= 89%Cu/ 11%O
                 1*16  16                                  
                           144 g/mol
Step by step process. . .
Write a balance chemical equation and identify the knowns and the unknowns.
25.0    50.0g  --->  ?g
P'4(s)  +  50'2(g) ---> P'4O'1O(s)

Determine the number of moles of the reactants by multiplying each mass by the conversation factor that relates moles and mass, the inverse of molar mass.
25.0 gP'4 * 1 mol P'4/123.9 g P'4 = .202 mol P'4
50 g O'2 * 1 mol O'2/32 g O'2= 1.56 mol O'2

Calculate the actual ratio of available moles of 0'2  and available moles of P'4.
1.56 mol O'2/.0202 mol P'4 = 7.72 mol O'2/ 1 mol P'4
Determine the mole ration of the two reactants fomr the balanced chemical equation.
5 mol O'2/ 1 mol P'4

Because 7.72 mol O'2 is available but only 5 mol is needed to react with 1 mol P'4, O'2 is in excess and P'4 is the limiting reactant. Use the moles of P'4 to determine the moles of P'4O'10 that will be produced.

Multiply the number of moles of P'4 by the mole ratio of P'4O'10 (the unknown) to P'4 (the unknown)
.0202 mol P'4 * 1 mol P'4O'10/1 mol P'4 = .202 mol P'4 O'10

and then i will add the yellow paper from the scanner in class. . .

How much water is in popcorn. . . .

In this lab we were suppost to find the mass of water loss from the certain amount of popcorn and calculate what percent of the original mass was the water given off in the popping. First we got a 1000-ml beaker and covered at the bottom with vegetable oil. Put foil over the top and it weighted 221 1/2 grams. Then we added exactly 28 corns and then it weighted at 225 grams. Pocked holes into the top of the foil then we lit that baby up. After all the popcorn was popped we let it set to cool and then weighted it at 2221/2 grams. We got that 1.9% of water was given of the popping.  mm then we got some popcorn for everyone:) it was a very good day lol

Metal Activity

Instructions: First we took a 24 plate that was 4x6 and the substances in the corrects numbering and lettering on the plate.

1st Column (A-C): 8 drops of copper(II)nitrate
2nd Column (A-C): 8 drops of magnesium nitrate
3rd Column (A-C): 8 drops of zinc nitrate
4th Column (A-C): 8 drops of silver nitrate
                  Then. . .
1st Row (A): place a small copper wire
2nd Row (B): place a small magnesium ribbon
3rd Row (C): place a few zinc granules

The Plate Results:

Cell letter.        Metal.       1.                   2.                 3.                  4.
                                       (Cu2+NO31-)  (Mg2+No31-) (Zn2+NO31-)  (Ag1+No31-)
   A                     Cu               NR                    NR                   NR                 PPT
   B                     Mg              PPT                   NR                   NR                 PPT
   C                     Zn               PPT                   NR                   NR                 PPT

NR= not reaction
PPT= precipitate

Observing this lab and the reactions that occured i noticed that the metal that reacted the most to the solutions was: Zinc and the metal that reacted the least to the solutions was: Copper.   From the most reactive to the least metals is: Zinc, Magnesium, then Copper

So then Mr Ludwig asked: So why in New York the Liberty girl is made of copper and not other metals? After seeing this experiment I knew why. With the statue having to deal with weather, copper was the metal that would not react or get destroyed by many elements.

Types of Reactions

•  Reaction 1: HCl+Mg-----> H2+MgCl2

What we did: Test tube 1/2 way full of hydrochloric acid, put a piece of magnesium metal in and then right away place a second tube on top. Once the reaction stops we got a matched flame and stuck it into the second tube.

What happened: A soon as the metal was put in, it bubbled like crazy and heated up the tube. Soon enough the metal was gone. . .  When the match was put in the tube, it made a loud high pitch noise. The hydrogen gas exploded and thats what caused the loud noise.

Belief: I believe that the gas that was created and the addition of the match caused an explosion, thats what caused the loud noise.

•  Reaction 2: Mg+O2---heat---> MgO

What we did: Grab a magnesium strip with a pair of tongs and light it on fire.

What happened: FIREWORK! The became a bright white light, the fire lit the metal quickly.

Belief: The magnesium strip and the fire caused a reaction that expanded, created the bright white light.

•  Reaction 3: Cu+O2 --heat--> CuO

What we did: Took a copper wire, used a sand paper to shine it up. Then we tongs we held the wire and lit it on fire.

What happened: The flames surrounded the whole wire and it was bright red looked as if the metal was melting. Once in awhile a bright little green color would show up and when it was done, the metal was burned black. If u washed it with water, the shiny copper would sort of show up.

Belief: I think that copper was such a strong substance that not even fire phased it just caused a little reaction, the fire couldn't meet coppers standards.

•  Reaction 4: (NH4)2CO3 ---heat---> NH3+CO2

What we did: We poured a small amount of ammonium carbonate into a test tube, then we heated up the test tube and shifted the scent it created.

What happened: To me it smelled like hair dye, it was very strong. My nose felt like it was burning and i thought my nose was bleeding but it just became a little runny. My eyes began to water cause it was so intense.

Belief: The fire increased the smell of the substance cause it already had a smell but after heating it up, it was defiantly a stinky smell!

•  Reaction 5: H2O2 ---mn2--> O2+H2O

What we did: We filled up a tube 1/2 way of hydrogen peroxide, and then we added a little amount of manganese dioxide. Immediately  we held another test tube over it. After the reaction was done, we lit a match and blew it a little out to where it glows, then stuck in into the top test tube.

What happened: The reaction in the tube turned all black, looked like black tar. When we put the small glowed match and it reflamed the flame.

Belief: The gas that was created was a conductor of fire or flames, it was an active gas that get the flame recreating.

•  Reaction 6: KI+Pb(NO3)2------> KNO3+PbI2

What we did: Put a small amount of potassium iodine in a test tube, then put lead nitrate into another test tube. Then we combined the too substances. . .

What happened: The two colors we started with were clear and when we joined them together, they made a bright some what powder substance.

•  Reaction 7: CuCO3---heat---> CO2+CuO

What we did: In a test tube was a small amount of copper carbonate, we covered another test tube over it and put it over the burner. When it was done reacting, we put a lit flame inside the top test tube.

What happened: When we put the flame match into the second tube, the burned substance made a gas the took the flame out.

Conductivity Lab

The idea of the lab was to see if different types of substances were able to conduct energy. We mixed 10 different chemicals with water and went to examine the conductivity. With a conductivity tester we put the two solid metals sticking out into the liquid and the meter showed the level of conductivity it had. Here is a graph showing our results: