Title of the Lab: Where's the Evidence? Guiding question: What are some signs that a chemical reaction has taken place? Hypothesis: Physical change is a sign that a chemical reaction has taken place, this could include color change, appearance change and a lot of other physical changes List of the Materials used: Notebook Zinc CuSo4 Pencil HCI Aluminum foil Baking soda CaCL Starch Vinegar Na2Co3 Iodine Sugar Heat(Lighter) Data Table with ALL observations (You get graded on this so make sure that you have included all observations, even if you didn't write them all down. Try to think about all aspects of the reactants and the product (basically all that went on during the reaction). Mixture Observations prediction before during after Baking soda and vinegar Baking soda a white powder while vinegar is a see through liquid It’s going to slightly bubble up Baking soda a white powder while vinegar is a see through liquid It bubbles up and rises to the top of the test tube/ physical change A lot less liquid than at the beginning, the color is white and stays like that Zn + HCI Zinc is a shiny metal, while HCI is a see though liquid The solution is going to change color and physical appearance Zinc is a shiny metal while HCI is a see through liquid During the experiment the mixture started bubbling up but stayed at level, It continued bubbling even after the first CaCL +Na2Co3 Cuso4+Aluminum foil Aluminum foil is has a metal surface and can change shape easily While CuSo4 is a light blue liquid I believe that it’s going to bubble up Aluminum foil is has a metal surface and can change shape easily While CuSo4 is a light blue liquid The mixture starts bubbling up but doesn’t change its level and parts of the aluminum start breaking off The mixture continues bubbling up but CuSO4 turns colorless Starch + Iodine Starch is a white powdery flour while Iodine is a see-through liquid I believe it’s going to change color Starch is a white powdery flour while Iodine is a see-through liquid The mixture turned dark black, you couldn’t see through it at all, when shook the hold tube turned black and stayed that way for a couple seconds The mixture stayed and didn’t change at all Sugar + Heat Sugar is white and contains many little grains while heat is fire coming from a lighter The sugar will change color Sugar is white and contains many little grains and the foil is a metal surface and the heat comes from a lighter The sugar slowly started turning yellow and melting a little while the foil was melting and making holes, the foil turned black and a lot of smoke was coming out. It stayed the same, the foil was black while parts of the sugar were white and parts yellow. Analysis of your results. Most of the results we got are accurate to our predictions we mostly predicted color change, and bubbling up. We knew that the reaction was over as soon as the strongest reaction finished in most cases this was first one, an example is a color changing reaction as soon as the mixture changed color the reaction was over. In all results something changed the mixture didn’t have the same physical appearance after the reaction. The products we started with were never the same as the products we finished with, they looked different and most of the times you couldn’t tell. Both chemically and physically the mixtures were different. Conclusion : The question was, what are sign that a reaction has taken place? Our hypothesis was correct, we stated that there was a physical difference, and there was, non of the products/mixtures stayed the same after the reaction, they all changed and looked differently, color and physical change happened. We learned that new substances are formed because there was a physical change from the outside, which made it look different but also a chemical change, because both the objects mixed and there for their chemicals mixed to form a new substance. The reactions did come to an end which we learned. The reaction came to an end , at the moment when they mixed and something started changing in their physical appearance as soon as movement and difference stopped happening in the test tube the reaction was over and that was a new substance. Through this we learned how reactions happen and how it looks from the front row, we got to see what actually happens Further Inquiry: Think about this experiment and the data you collected. Would you make any changes to the method/procedure? Do you have any further questions? I think this experiment was quite successful and I wouldn’t change a lot. The only thing I would change was leaving the mixtures for longer periods of time a day or two and see is there any changes. The only question I have do they ever come calm down, if the experiments bubbling does it ever stop --