Copper Foil

Purpose- The purpose of the lab was to become more familiar with the lab. Also to make qualitative and quantitative observation about physical and chemical changes during a chemical reaction.
Materials- Beaker (150-250)
Copper(II) sulfate pentahydrate- caution, toxic substance
Scoopula
100ml graduated cylinder
Stirring rod
Thermometer
Small square of aluminum foil
Procedure- This lab is unique in that it serves both as an introduction to a laboratory environment and as a review. It demonstrates the terms and concepts we have learned recently learned in the lecture. Thus, as you read and follow the procedure, be sure to answer all the questions that are posed to you in the spaces provided on your paper.


1. Form a group of TWO OR THREE PEOPLE. Go to your lab station after taking all appropriate safty precautions that we discussed in the safety lecture. (YOU MUST WEAR SAFETY GOGGLES AND APRON.)


 QUESTIONS AND ANSWERS


2. You will find in front of the beakers at your station, the 100 ml graduated cylinder, a scoopula, the thermometer, some aluminum foil, and a container holding some cupric sulfate pentahydrate. Go to the appropriate source and add some water in your beaker. The exact amount is not important, although it should be between 75 and 100ml. Make sure you write down how much water you put in the beaker though.
     QUESTION- Make ONE qualitative and TWO quantitative observations of a physical property of the water in the space below. Be sure to make it clearly distinguish which is which.


      Qualitative- The water is clear.
      
      Quantitative- 1. The water is 79 ml
                             2. The temperature is 22 degrees Celsius


3.  Now, using the scoopula, obtain some of the copper(II) sulfate pentahydrate. Again the exact amount is unimportant, but your scoopula should be about one quarter filled with the solid ( Ask the teacher if you need help with anything.) Place the copper into the beaker and stir with the stirring rod until all the solids have dissolved.
    QUESTION- You have just made a mixture of CUSO4 in water. Is this mixture homogeneous or heterogeneous? Explain.


     Heterogeneous because the water turned blue from the copper solids.


4. Obtain the aluminum foil sample in front of you and crumple it up into a loose ball. Then place the ball carefully into the mixture and stir gently for 15 seconds. Write down a detailed observations of everything you see in the space below. At least one of the observations should be quantitative.


     OBSERVATIONS AFTER ADDITION OF ALUMINUM-
  
    Nothing really happened the foil kinda bubbled but other than that the quantitative is that the volume of the beaker rose up more so its 80.


    Did a chemical change occur ethe additional of the aluminum? Explain.
Yes there was a chemical change.  The color of the water changed to a deeper blue, and the temperature changed a little as well.


5. Make sure your scoopula is clean (rinse with tap water and dry with a paper towel if not) and obtain a large scoop of sodium chloride from the labeled container  Add the NaCl to the beaker containing the copper (H) sulfate - aluminum mixture.  Stir until all of the sodium chloride is dissolved and make detailed observations of everything you see in the space below:  Again at least one of the observations should be quantitative.
OBSERVATIONS AFTER ADDITION OF SODIUM CHLORIDE: 
- It turned into a heterogeneous mixture
- Black chunks floating, it sticks to the alluminum
- when chunks are stuck to the alluminum, they appear to be red


Did you just see a physical change or a chemical change? Explain.
We saw a physical change; the black chunks are still floating in the solution.


How many different states of matter do you observe? Describe, from your observations, what they are.  Which do you see in the beaker right now?
We see 2 different states.  Liquid and the chunks of black and red.
we see both liquid and solid


Any idea what the red solid is that dropped to the bottom of the beaker?
Copper


6.  After approximately 10 minutes, take your beaker over to the large funnel and beaker and slowly decant (pour) your mixture into the beaker.  The instructor will show you a way to do this that will insure that all the liquid ends up in the funnel.  Then clean your beaker thoroughly with soap and tap water and then a final rinse with distilled water.  Make sure our lab station is clean, return all safety equipment to its proper location, then return to your desk.


DISCUSSION: You have just observed a chemical reaction between copper ion and aluminum, which produced copper metal, hydrogen gas, and aluminum ions.  During the course of the reaction, you should have made several different observations that are all indicators that a chemical change is occurring.  From the discussion in the class list the indicators below:
                                                   Indicators of a Chemical Reaction
1)  Bubbles form without adding heat
2)  Heat is produced
3)  Precipitate forms
4)  Change of color