The last experiment I've been doing over the past week was the determination of the hardness of a water sample. The experiment was split into two days, the first was the standardization of our EDTA solution (meaning we figured out the molarity (which is moles/liter) of the solution, for those who don't know (hi mom! ^_~)), the second day was the actual testing of a water sample. We used water from a fountain on campus that I happened to have had from the previous day.
We start by titrating a 'blank' or a sample with only magnesium chloride, as we want to know the exact volume of EDTA used for it, so we can subtract it later. For a more complex explanation of the experiment you can go here.
Our blank with indicator.
My partner getting our calcium sample ready.
Preparing for titration, the paper towel helps to spot the color change more easily.
First titration of our calcium sample on the left, our blank on the right for comparison.
EDTA, or the big name there on the bottle, lol.
The magnesium chloride sample.
Some hydrochloric acid.
Eriochrome Black T indicator, blue in distilled water, turns our samples red/pink.
These are volumetric pippettes that read to the hundredths spot. We used 25.00 mL ones for our standardization and then 50.00 mL ones for our actual test of a water sample.
First sample of fountain water, titrated to the end point.
Sample two before titration.
Endpoint titration three.
Materials desk, it has the magnesium sample, the indicator, and some hydrochloric acid that we didn't use.
These are the bulbs of the volumetric pipettes.
Random shot down the classroom.
Another students table, some very pretty colors here!
So I won another mini-contest like thing. :) A random act of kindness give-away of make-up that the owner of the blog, Peace, Love + Sparklesdidn't want anymore. This was her first round, but she has already done one more, and is on the third right now! You just have to go and comment. To see a list of what I got with swatches, check out her original ROAK #1 post here. Oh and her house must smell divine, or maybe it was a perfumed bag, because when I opened the package it smelled so good!
So, last semester, I had so much fun in Human Anatomy and Physiology, and the info just came so naturally and easily to me. So much so, apparently, that I am now the A&P tutor at my school! It is an actual, paying job, and I've been so excited about it. Today was my first day, and as I imagined, it was fairly slow. The only student I had come to the open lab, was actually a girl I had studied with last semester! She is taking A&P 2 over the summer, so even though I haven't taken the class, I looked it over with her, and basically, she taught me a bit, and I was able to impart the small amounts of knowledge I had about the heart and help her cement that knowledge into her brain. I think I'd be able to take their quiz tomorrow and pass! So, of course, you know I had to take pictures and do some diagrams! So here is the heart, and it's many intricate parts.
This caturday, I introduce to you Obie, the bearded dragon!! :D She is the pet of my nerdy co writer, Cymone. Here she is eating oooey gooey silkworms. I think she is adorable, she looks so happy to see those squirmy little guys.
Chillin', huggin' a chair or leg post. lol
And then tiny obie!
And then our usual crowd!
and a not so regular, Paul the evil cat! Glaring at me all the way across the room.