1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Resource for chemistry letter and symbol definitions/values in equations

  1. Jan 21, 2013 #1
    1. The problem statement, all variables and given/known data

    I have a chemistry teacher who discourages students from asking questions (long story, but he's just not a good teacher). We have an online textbook, which fails to explain a lot when it comes to formulas. One thing I want to understand is what the different letters and symbols in formulas and equations mean. Like when I see a "Q" or a "Δ" in a formula, I'd like to know what those things actually mean. I don't feel like memorizing a formula does me much good if I don't know exactly what those formulas are looking for, and feel I will gain a much better understanding of the material if I understood how different aspects of chemistry are formulated together in the different equations. In both chem I and II, all our teacher does is hand us formulas, then has us plug arbitrary numbers into those formulas, but doesn't explain what those numbers actually represent, so none of us really have any idea what we are actually calculating.

    2. Relevant equations

    ln [A] = –kt + ln [A]o

    These are just a couple, but I don't know what the "e" "k" "t" "o in [A]o" "R" or "T" means.

    3. The attempt at a solution

    Asking my teacher has proven futile, and I am in a small school so not sure who else would be good to ask. I have tried a web search to no avail and checked my local library and bookstore to no avail as well. I am open to any materials I could get my hands on that will help me to know what it is that I'm actually calculating so I may better understand what I am doing.
  2. jcsd
  3. Jan 21, 2013 #2


    User Avatar

    Staff: Mentor

    e - http://en.wikipedia.org/wiki/E_(mathematical_constant)
    (note: what you wrote is wrong, correct formula is [itex]e^{\frac{-E_a}{8.314T}}[/itex], where 8.314 is a value of R)

    k is a rate constant (in this context)

    Ea is an activation energy

    t is time

    [A]0 means concentration at t=0 (initial)

    R is the ideal gas constant

    T is temperature

    There IS something very wrong about the situation you describe and about things you don't know, but I have no idea whom/what to blame.
  4. Jan 21, 2013 #3
    Thanks for filling me in on that information. I did manage to find some additional information on the matter. The key word I was missing was "reference". Once I typed that into the search engines along with chemistry, I found a handful of useful reference charts, lists, etc., that has all of the information.

    Anyway, our professor at our college is one of those types who is extremely intelligent, but has absolutely no social skills and is not good at conveying what he is trying to say to others. He is confusing, because he tries to be nice by baking us cookies from time to time, tries to tell jokes here and there (that usually fail miserably), and in some ways comes off as real nice. However, if you ask a question in class, his first step is to demean or belittle you in some way, then he will answer the question in such a convoluted way you can't understand it or will wander off on a tangent without ever even answering your question. A lot of students are very frustrated with him, and I am literally the only person in my class who got an A in Chem I last semester. Anyway, I really don't mind the situation so long as I have resources outside of class that I can utilize to gain a better understanding. Thanks again for the help.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook