Chemical Reactions Lab

Chemical Reactions Lab

Guiding Question: What are some signs that a chemical reaction has taken place?

Hypothesis: I think that the signs of a chemical reaction are change in color, change in temperature, gas being released and precipitation.

Materials:

·        Spatula

·        Graduated Cylinder

·        Starch

·        Iodine

·        Candles/ matches

·        Goggles

·        Beakers/ jars

·        Sodium Carbonate

·        Calcium Chloride

·        Hydrochloric Acid

·        Copper Sulfate

·        Aluminum Foil

·        Zinc Pieces

·        Baking Soda

·        Vinegar

Procedure:

Baking Soda + Vinegar = Add baking soda into a graduated cylinder, then pour in some vinegar, and record the reaction.

Copper Sulfate + Sodium Carbonate Solution = Add the baking soda (sodium carbonate) into the graduated cylinder and then pour in the copper sulfate

Zinc Piece + HCL = Take a small piece of zinc and put it into the graduated cylinder then pour over the HCL into the graduated cylinder.

Calcium Chloride + Sodium Carbonate = Add the baking soda (sodium carbonate) into the graduated cylinder then add calcium chloride to this substance.

Copper Sulfate + Aluminum foil piece = Add a small square of the aluminum foil into the graduated cylinder  then pour over that a small amount of copper sulfate, enough to completely cover the foil.

Starch + Iodine = Take a teaspoon of starch and put it into the graduated cylinder then with eyedroppers I poured in 1-2 squeezes of iodine.

Reaction	Observations before reactions	Prediction	Observations during reaction	Observations after reaction
Baking Soda + Vinegar	It is in powder and liquid form	It will foam and bubble	The foam created, rises and bubbles and fizzes	The foam settles and the baking soda has dissolved
Copper Sulfate + Sodium Carbonate	Again in a separate liquid and powder form	It will explode	Mixture rises foaming very quickly	Precipitation occurs
Zinc + HCL	A small pebble of zinc and liquid	The zinc will cause bubbles to form	Slow reaction Fizzy Bubbles surrounding the zinc	Slow reaction, end result not seen
Calcium Chloride + Sodium Carbonate	Separate  substances	To foam	Foggier water, not much of a reaction	Precipitation
Copper Sulfate + Aluminum Foil	Foil and liquid	To dissolve quickly	Blue Color fades Bubbles surround the foil	Aluminum becomes brown and becomes shreds
Starch +Iodine	Separate Substances	To explode	Mixes Slowly and must shake to mix	Turns a deep purple when water is added
Sugar + Heat	N/A	N/A	N/A	N/A

Analyze and Conclude:

1. How do the results of each reactions compare with your predictions for that reaction? The results of the reactions were slightly different from the predictions we had because a lot of them predictions were things such as, "It will explode" and a lot of the things did not explode.
2. How did you know when Reaction 1 was over? We new the reactions was over because the fizzing had subsided and the sodium carbonate had dissolved into the vinegar and had become a new solution.
3. Was the product of the reaction in Part 1 a solid, a liquid, or gas? How do you know? The product was a liquid and we knew because we saw the end product.
4. Was the product of the reaction in Part 3 a solid, a liquid, or a gas? How do you know?
5. How do you know if new substances were formed in each reaction? The end result in part 3 was a liquid with precipitation which were small pieces of solid so it was a mixture with solid particles.
6. What sense did you use to make observations during this lab? How might you use scientific instruments to extend your senses in order to make more observations? We used sight to to tell the outcome of the reaction We could use instruments to maybe tell the different properties of the end result of the reactions.