Week 25

Week 25 in chemistry was not very much of a week for me. I was only in class for 2 out of the 4 days, but was still able to learn plenty of valuable information that we will continue with for the next upcoming weeks. We started with a lab in which we placed copper chloride into H2O. In doing this, the once brownish copper chloride turned the H2O blue. This mixture was in the same type of trough that we used for electrolyzing H2O, so, we electrolyzed the solution. Up one test tube went a clear liquid, and the other was a bronze liquid, which we could identify as the copper. So what does all this mean? In doing this lab, we determined that if a compound is soluble in water, it will separate into its individual ions. Also, these individual ions would be affected by the polarity of the H2O. The copper was positive, and chlorine negative. So, the copper was attracted to the slightly negative oxygen in the H2O. The chlorine ions were attracted to the slightly positive hydrogen atoms of the H2O. We also know that some compounds are soluble, some aren't. Also that some compounds are polar, and others aren't. The last thing we took from this lab was the common phrase Like Dissolves Like. This states that in order to dissolve a polar compound, you need a polar solvent. You also require a non polar solvent to dissolve a non polar compound.
We were all asked to create electroscope. These electroscopes were simply made and showed whether an object had charge or not. My electroscope was a glass jar with a ballot aluminum foil on top. Sticking into the ball was a paper clip that went inside of the jar with two aluminum foil leaves hanging at the bottom. If a charged object was brought close to the ball, the leaves would separate and repel each other. Through induction these leaves would separate. The paperclip had a neutral charge throughout the entire thing. Once the charged object was brought near, the electrons would try and get as far away as possible. They moved down the paperclip causing an unbalance in the leaves. Now both leaves were negatively charged, so, they repelled each other. For such a short week in Chem, many important concepts were revealed which will continue to be a gateway through to many more additions of chemistry and our studies.