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Analytical Chemistry: L#00 An Introduction

In all of the physical sciences, there is a high need to be analytical.  After all, being analytical is how we know with scientific certainty that what we hypothesize and theorize is legitimately true.


In a way, the physical sciences have an advantage in the analytical realm that the life sciences and social sciences don't have; it is exceedingly easier to get pull numbers out of experiments in the physical sciences than in either of the other two types of sciences.  After all, the life and social sciences have too many variables which can not be controlled for, for one reason or another.  After all, in economics (a social science), it is immoral to make some people be in poverty while making others financially prosper for any reason, much less to get numbers for analytics.  It is also immoral in medical science (a life science) to infect one group with disease while keeping others disease free for any reason, much less to get numbers for analytics.  So physical sciences is lucky to have fewer situations of amoral or immoral experiments to get numbers for analytical study than social or life sciences.

Muahahahaha
The final number matters here.  After all, in medicine, where you do want 5 mg of a medication, you do not want 5 kg, because that 5 kg will kill you.  The soda industry knew to recommend drinking a gallon of water a day in order to "stay hydrated" (read "keep lining our pockets"), because drinking much more than that will yield a higher likelihood of developing hyponatremia, a condition of over-hydration where the concentration of salt, sugar, and other vital compounds in your blood becomes too low (or to put it another way, they become too dilute).  This can be fatal.  So yes, even in ad campaigns, using the correct final number is vital.

We will constantly be working with matrices; not in a pop culture or a mathematical sense, but chemical matrices, which is the structure the chemical system makes up.  Sometimes this means ions, other times this means the chemistry forms a sponge-like structure.

Where's Neo when you need him?
Calibration is important within the range of study.  This is a method of making absolute certain that the device you're working with is responding correctly to stimuli.  After all, you don't want a cop to apply an uncalibrated breathalyzer when you're sober, because if you recently had vinaigrette on your salad, that uncalibrated breathalyzer will show you as intoxicated.  For any response curve like the breathalyzer, there is a nonlinear range from the origin of the graph to a certain critical point.  Past that critical point is the linear range, where it's just a horizontal line.

In this lecture series, I will cover the analytical methods for one particular physical science -- non-biological chemistry.  This process deals not only with the typical quantities of chemistry -- mass, volume, moles, concentration, etc. -- but also with statistical analysis -- probabilities, z-scores, distributions, etc.  This is a course for creating a more accurate intuition about the aspects of life which directly impacts us.


Take that as you will,
K. "Alan" Eister Î”αβ

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