Chemical Lab

Introduction:
This is a lab that is purposed to help us become familiar with the laboratory and to make qualitative and quantitative observations about physical and chemical changes during a chemical reaction.

Physical Change: A change during which some properties of a material change, but the compsition of the material does not change.
Chemical Change: A change that produces mater with a different composition than the original matter.
Qualitative: An observation that depends upon the Quality.

Quantitative: An observation that depands upon the Quantity.

Idicators of a Chemical Change

Color Change
Temperature Change
Bubbling without Heat
Solid that drops out of a liquid (A precipitate)
Hypothesis:

We think that the temperature will rise whenever we add something to the mixture due to the fact that adding more think will cause a chemical reaction and create heat that way (the creation of heat will indicate that it is a chemical change as well)
 Materials:

• Copper (II) sulfate pentahydrate
• Scoopula (copper is toxic)
• 100mL graduated cylinder
• Stirring rod
• Thermometer
• Small square of aluminum foil

Procedures:

• Form lab group with 2 or 3 people
• MUST wear safety goggles and apron
• Collect all the needed lab materials
• Fill beaker up with water, anywhere between 75 and 100mL
• Use the scoopula and get some of the copper (II) sulfate pentahydrate. Fill scoopula about 1/4th of the way (doesn't have to be exact)
• Place the copper in the beaker containing the water
• Stir  with the stirring rod until all the solid has dissolved
• Make observations
• Crumple the small aluminum foil into a loose ball
• Place the aluminum ball into the solution
• Stir gently for about 15 seconds
• Make observations
• Clean scoopula with water and dry with a paper towel
• Get a large scoop of sodium chloride (NaC1) from the labeled container
• Add NaC1 to the beaker containing your mixture
• Stir until NaC1 is dissolved 
• Make observations
• After about 10 minutes, take beaker to large funnel and beaker and slowly pour mixture into the beaker
• Instruction will then show you a way to do this to insure that all the liquid ends up in the funnel.
• Clean your beaker thorughly with soap and tap water
• Rinse beaker with distilled water
• Clean your lab station
• Return all safety equipment to proper location

Data: 

• When we put 90mL of water in the beaker it was clear, with a few air bubbles. The temperature was 23.5 degrees celcius. 
• When we added the copper(II) sulfate pentahydrate the temperature slightly went up to 24.0 degrees celcius. Adding the solid caused it to rise to 90.5 mL. After stirring for a long time, the solid dissolved. The mixture was then blue and clear.




The Mixture is a light blue


• After adding the foil, the temperature stayed the same but it rose to 91.0mL. We stirred as directed for about 15 seconds. The solution stayed blue and the foil floated in the mixture.
• Once we added the sodium chloride, the aluminum foil changed colors and started to disinigrate. The solution got darker. The temperature went up to 32.9 degrees celcius.

The Tinfoil is able to foat upon the surface of the water;
the chemicals in the tinfoil cause the copper in the mixture to separate from the liquid.



The Copper during the Chemical Reaction drops to the bottom
(a precipitate)



Discussion:

• Adding the sodium chloride to the copper(II) sulfate pentahydrate and aluminum foil mixture caused a chemical reaction.

Conclusion:


There was a chemical reaction when we added the sodium chloride to the solution. The way that we know it was a chemical reaction is because there was a formation of precipitate and there was also a change in temperature, a creation of heat without another source of heat. The chemical make up of the tinfoil when clashed with the Sodium Chloride caused the copper in the mixture to drop out and settle at the bottom (a precipitate). There was also a slight change in the color of the mixture, which also means a chemical change.