I made a Prezi about the periodic table. It has alot of great information! Check it out!
http://prezi.com/ymjqovku52zd/the-periodic-table/
please just watch the show rather than editting any of the work. thank you! ENJOY! :)
-katrina
Wednesday, November 10, 2010
Tuesday, November 9, 2010
Conductivity Lab
We recently have been learning about atoms and we are talking about their break down or build up into ions. Certain atoms of substances are much more likely to become ions than others. For example, Sodium has an electron configuration of 1s22s22p63s1. Because of this, Sodium is often found in its ion form Na+, this means that often sodium looses an electron to become stable like neon. This makes it a pseudo-noble gas with the configuration of 1s22s22p6. This was just one example and we figured if sodium was likely to make ions then so were other elements. We constructed & preformed a conductivity lab. In this lab we tested 8 different substances dissolved in distilled water with the purpose of finding out which solution held a greater concentration of ions. For each solution we would record our prediction of how high the ion concentration would be ranging from none to very high. From here we tested with a simple, store-bought, battery-powered, ion concentration detector. This only detected from none-very high, it gave no numbers & no precise measurements. After we tested all of these with this conductivity tester, we tested these substances with the conductivity probe. This probe can accurately measure these solutions to give us even a better idea of how highly concentrated each solution was.
Here is the data we collected:
Substance Prediction result w/ tester result w/ probe (uS/cm2)
Methanol high very high 249.2
Calcium Chloride medium very high 246.6
Albumin medium very high 248.7
Cupric Oxide low low 22.4
Ammonium Sulfate very high very high 249.3
Glucose/ Starch low low 35.0
Citric Acid high high 249.3
Sugar Water low low 16.1
From this data we can conclude that certain dissolved substances such as Ammonium Sulfate and Citric Acid have a much higher concentration of ions than substances like Sugar Water and Gluscose. In some cases, substances wouldnt always dissolve well in the water to give a very accurate concentration reading (Ex: Cupric Oxide). Overall, we learned that many dissolved substances have concentrations of ions whether high or low.
Subscribe to:
Posts (Atom)