Chemistry: Usually the bane of a science student’s existence. However, by remembering 6 major things you learn from the Chem I (1061) class at the University of Minnesota, you’ll find chem will slowly become a little easier. Let’s begin!
1. PV = nRT
Honestly, if you have gotten this far without burning this equation into your brain, then I applaud you. This equation is one of the fundamental equations in chemistry, and can be used to describe many gas laws with one simple calculation. The symbols in this equation are fairly simple, P = pressure of the gas, V = volume of the gas, n = the number of moles of gas in the sample, R = the universal gas constant (0.0821), and T = temperature in Kelvins. It’s fairly easy to manipulate this equation to find any of these variables for one equation, and can be combined with any other gas equation to find the answer you need.
2. KELVIN! KELVIN! KELVIN!
Ok, no one really understands why we still use Celsius and Fahrenheit to measure temperature when every single chem equation uses Kelvins. Seriously, would it kill someone to condense all of these units into just one that everyone uses all the time? Apparently not haha. Kelvin is what the chemists are using these days, and if you don’t use Kelvins in an equation, you could be looking at a very wrong answer. Whenever you see a temperature in a problem, just add 273 to it to convert it to Kelvins right away. You may not need it in the end, but it’s better to do it first rather than forget, and mess up your calculations because of it.
3. Moles Aren’t Just Underground Creatures
In order to determine whether you have the same amount of oxygen and hydrogen, moles are the best way to compare their amounts. Simple, yet incredibly helpful in stoichiometry problems, the mole is something that you will use for the rest of your chemistry studies, and maybe beyond if you actually use chemistry in your day to day job. Again, it seems like more work at the beginning, but it really saves you time in the long run.
4. VB Theory Saves Lives…..or Exam Grades
The Valence Bond Theory simply states that a covalent bond forms when orbitals of two atoms overlap and a pair of electrons occupy the overlap region. Electron pairs and bonding takes up a lot of the semester in Chem 1061, and learning what they can and can’t do in their respective orbitals is a big part of understanding how they actually work. The valence electrons will become your best buddies soon. They follow very specific rules in order to create covalent bonds (which the professors love grilling us with). Once you know that these valence electrons are the key to any covalent bond, you already have half of the problem solved!
5. VSEPR Theory Determines Molecule Shape
Valence-Shell Electron-Pair Repulsion Theory says that to minimize repulsions, each group of valence electrons around a central atom is located as far as possible from the others. Every molecule has a certain shape, even if we can’t see it right away. And even when we can’t see it, you still need to know how to determine the shape of a molecule. While there is a table that you can find about the angles and specific names of these shapes, I am going to tell you the simplest way to start out. When drawing these molecules, always make sure that the “groups” or other atoms bonded to the central atom are as far away as possible from each other. They need to be far enough apart that they won’t affect each other, and this can easily be solved by attaching them to the corners of the central atom, or if it is only two groups, then simply put them in a straight line. Easy!
6. You Probably Won’t Get an A, and That’s Ok
This class is arguably one of the hardest on campus. Ask any student who has taken chemistry, and they have horror stories to tell you about tests gone wrong and practice problems that take up half a page. It may sound frightening, but as long as you pay attention, study in small periods over a long time, and take care of yourself, it will be OK. Don’t feel like you failed if you didn’t get an A. There are curves for the tests, and the people who are getting A’s are wicked smart. This doesn’t mean you aren’t, it just means you have to work a little harder for it. Be proud of what you do in this class, because you’ve worked hard for it!
All in all, this class shouldn’t be that hard if you put the work into it. Like everything in life, there will be ups and downs in this class, and probably some moments when you question why anyone would voluntarily chose chemistry for their major. But hey, maybe at the end of this class, that person could be YOU!