Reaction lab

    Sophia Laura         

Sophia Laura   

Mrs.Medenica

Science

15 November 2011

Chemical Reactions Lab

Investigation question: What are some signs that a chemical change or reaction occurred?

Hypothesis:I think that the chemical and physical properties will change during the process, for example, size and maybe color.

Materials:

spatula

graduated cylinder

stirrer

candle

matches

goggles

baby food jars

Reaction table of elements

Reactions	Observations before reaction	Predictions	Observations after reaction
baking soda (soda bicarbonate + vinegar)	A white powder and a nasty smelly liquid that you usually put in salads.	It will change size and rise up.	Raised the  up when we put the vinegar to the baking soda and it is bubbly and foamy.
sugar + heat	A silver white aluminum paper and white sugar.	It will change colour and become caramel.	The color changed to black and yellow and then became caramel.
Copper sulfate sodium carbonate solution	A blue liquid with a transparent liquid.	It will change colour.	The colour changed - it became blue and it made bubbles.
Zinc piece (HCI)	A rock stone and a transparent liquid that burns your skin.	Becomes bubbly.	It became warm and it made bubbles and it had a nasty odor.
Calcium chloride + sodium carobrate	Two transparent clear liquids.	That it will change colour.	It became white and it made bubbles.
Copper sulfate + aluminium foil piece	Light blue liquid and a silvery metal piece of paper.	That will change color and will make bubbles.	The aluminium paper became red and even the water changed color.
Starch + iodine (I2)	White powder and red bloody liquid.	Colour changes.	It became yellow black and purple.

Analysis of Data: There were a lot of patterns in many reactions there were bubbles and the color in most of them changed. Another thing that was happening in the reactions was that in a lot of them the size and state changed, like in one of them it raised up and it grew while in another one it became from big to small -it shrank and it enlarged in some of them, not a lot of them though.

Conclusion: What are some signs that a chemical change or reaction has occurred? Well, at the end of the reactions we noticed a lot of things that happened. As i said the color changed in most of them and the size in some of them and in a lot of them bubbles continued showing up like in the baking soda that it is clear that they will come and in the (calcium chloride + sodium carbonate). Well, from the guiding question it seemed that the things that were stated in the guiding question actually happened in the experiments that we did. My hypothesis was actually pretty correct because the things changed during the process. Actually,  we knew that it would happen because it always does in an experiment. But I was pretty close because the physical properties like the size, state changed and that was one of the things I mentioned in my hypothesis, and the color too so I was actually right in my hypothesis. First of all, now I understand better how to do a lab and my observations. Actually I found out a pretty interesting thing while doing this lab. It was that chemicals are dangerous (some of them) and I understand better in what we are talking about in science class.

Further inquiry: What i think about my data is that part of it was correct and some of it was incorrect, because I got messed  up in what places I was supposed to put my observations. For instance, for the first one I put predictions first and I got mess up and had to resolve it. It was sort of hard to fix it but in the end  I made it. Probably, I could have improved it if I explained better what the material was. Next time I would write more and put more info into my observations. I just have one question - one of the experiments did not really make sense because from clear it became white. Well, it changed but it did not explode or something like that. I think that either the formula is wrong or we did something wrong with my partner.