Just the Beginning

Our very first blog addresses our very first lab with our very first objectives:

1. The difference between pure substance and a mixture?

2.The significance of the technique used?

3.Can you mathematically support your conclusion?

4. How can you validate these results?

 The purpose of this lab was to determine if a hydrate was a mixture or a pure substance. Well what's the difference? A pure substance contains only one kind of molecule/atom while a mixture is composed of different pure substances. The significance in the technique we used to test this question was basically how it supported the law of definite proportions... XY + H20(s) --heat--> H20(g) + anhydrous(s). Now, chemistry can be intimidating if math isnt your best subject. BUT have no fear. What this equation means is when heat is applied to a substance combined with water (hydrate), the product is water in the form of gas and a solid substance (anhydrous). The rest is easy, after calculating the percent composition of the anhydrous a conclusion can finally be made. This conclusion can be mathematically supported by the percent composition calculations. If they vary, the hydrate must be a mixture. So of course, if there is a specific percent, it must be a pure substance. I guess Ms. Gardner helped us cheat a little by telling us the percent "we should have gotten": implying the specific percent composition. However, the percents from all 3 groups seemed to be reasonably close to that percent (which was 48.8%). Lastly, validating these results requires calculating percent error. The End (of the beginning).





Matter Classification 
http://schoolsites.schoolworld.com/schools/ThousandIslands/webpages/eoliver/files/matter%20&%20energy.pdf