Date: 
         Fri, 20 Nov 1998 18:07:23 EST 
    From: 
         Saltzie@aol.com [Add to Address Book] 
  Subject: 
         Re: Contributing 
     To: 
         acejizhang@mailexcite.com


  November 15, 1998

  Study Guide for Chapter 5
  or: How I bested Ji in Chemistry
  by: Captain Nemo

  Part One:
          Welcome friends to the first edition of Captain Nemo's study guides for the
  Chemistry impaired.  These guides will be released periodically usually when I
  figure out the chapter.  This first part is the guide from pages 161-173 in
  the book, mostly on the equations.  So without futher ado, let's dance.
          The chapter is name Stoichiometry, though the book only spends about 3
  sentences on what that means.  To sum it up, al the stuff we have been doing
  has been leading twoards us doing full chemical equations, like these.  Once
  mastered, the student should be quite proficient at chemical reactions (in
  theory).  So, what does this mean to the average schmoe?  Not much.  But it's
  kinda interesting.  Allright, not interesting at all, but for all you busy
  bodies who have know the definition of everything, this paragraph is for you.
  Now, on to the meat of the chapter: Equations.
          For all of those who would like a short, to-the-point study guide, tough
  break.  But the again, you're getting this free at your leasure, so suck it
  up.  Anyway, while completeing this assignment, I was approached by a shady
  character known only as Ace Ji.  Ji, who has an excellent webpage, is a very
  good student.  So good in fact, that I was overcome with confusion by his
  request for help on these equations I had to sit down and re-process it.  Now
  our friend Ji is not very patient, especially to us schmoes who always come to
  him for help.  So, I summed up the steps to the equation in five words, which
  I will share with you now:
                                  It's All In The Ratio
  That's it.  For those of you who have been siting here wondering a).  What
  drugs is this guy on? b).  Where can I get some?  c).  When will this end?
  you can stop reading, those five words are the chapter.  Simply, all of these
  equations are the equations we have been doing, and adding in the ratio.
  Let's examine one:
  (p.  173 #9)   

  Calculate the number of moles of oxygen gas will be required to completely
  burn 1.06 moles of methane, CH4 to form carbon dioxide and water.

  So let's cut out all of the excess they give you.  The best way to do this is
  to write out and balance the equation:

  CH4 + 2O2 -----> CO2 + 2H2O

  Very simple.  Now, let's find the two reactants.  Looking at the written
  problem, we need to know the amount of moles of oxygen and we know the amount
  of methane.  You may be wondering why certain phrases are italicied.  The
  easiest way to find the reactants is to find what you need to know and what
  you know.  Now that you know this, you can look at the two reactants and find
  The Ratio.  Refer to above where we discussed the chapter.  This is the ratio
  that it is all about.  After this it's all just changing from moles to grams
  and back.  The ratio (drumroll please) is 2 oxygen to one methane.  That,
  friends, is all you need.  However, one may ask: "How do we know if it is 2/1
  or 1/2?"  Well, just see what you need in the equation (for all of you who
  want to do this equation indepently, something not encouraged in school, below
  is a spoiler.  Just a warning.):

  1.06 moles CH4 * 2 mole O2/1 mole CH4= 2.12

  See, nothing to it.  Find The Ratio and the rest is just grams---> moles.  For
  all of those who are using this for their note card, here are some steps.

  1).  Sometimes equations can be intimidateing.  It seems that the science
  folks who make these want to brand it in to our mind by making them as
  confusing as possible.  So take a deep breath, look at the problem, scream
  "BRING IT ON", and drive all fear out of your head.

  2).  Write out the balanced equation.  For the more complex problems, this is
  a must.  Also lable your amounts.

  3).  Convert everything to moles.  The g-m-m-g pattern can be kind of
  confusing to the layman, so just remember this, and look at what they need.

  4).  Find the reactants.  What you have and what you need.  You may want to
  write them seperately.

  5).  Find the Ratio of the reactants.  --'nuff said on this.  It's all in the
  ratio baby.

  6).  Use the Ratio to convert what you have to what you need.  Look at the
  above equation for help.  
   
  7).  Convert back to Grams.   If necesarry.