titrations, pH and logs

Since many of you have never seen a titration in practice, I thought I’d share this video so you can get a clear picture of what’s happening!

In addition to that, I found one on pH calculations including some background on logarithms.  I think this might help if your math is a bit rusty there!  Just make sure you know how to use your calculator on the exam…

Once you’re done with the video, you might want to use this quiz to check your understanding.  Instant feedback is very helpful in studying!


A little more on solutions and mixtures

Yesterday in class we had a question about solutions–they are not limited to solids dissolved in liquids!  Some alloys are solid solutions, and these are very important to the semiconductor industry.  For example, the solid solution used in an LED can determine the color of light it emits.  If you’re curious and want to learn more, here’s a quick tutorial on solid solutions–you might not have the background to completely understand everything yet, but it’s a nice introduction to some interesting concepts.

Of course, gases can form solutions too.  Without the dissolved oxygen in water, fish would be unable to breathe!  Gases also form homogeneous mixtures with other gases.  My lab has gloveboxes, which rely on a catalyst to keep an inert gas atmosphere inside.  We sometimes have to regenerate the catalyst using a gas that’s composed of 5% hydrogen in nitrogen.