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<div class="moz-cite-prefix">On 9/26/22 13:32, wrote:<br>
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<div dir="ltr">Dear Dr. Bounds, </div>
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<div dir="ltr">For the question you just posted in the
examples, how would you determine the bounds for the solver
calculations? How did you know the upper bounds was equal to
0.6? Do you just make a guess and see if it makes the
original equation equal to 0? I may have missed this in my
notes. <span></span></div>
<div dir="ltr">Please get back to me as soon as you are able. <span></span><span></span></div>
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<p>Dr. Bounds -- that's funny... Assuming it was a Freudian slip
based on the question...<br>
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<p>So in solving these we have to remember that our
CONCENTRATIONS/PRESSURES can never be negative. In fact, we have
carefully constructed our ice table so we can enforce this
constraint. With that said, look at the two term in the law of
mass action that could become negative.</p>
<p><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mo
stretchy="false">(</mo><mn>2</mn><mo>−</mo><mn>3</mn><mi>x</mi><msup><mo
stretchy="false">)</mo><mn>3</mn></msup><mo
stretchy="false">(</mo><mn>3</mn><mo>−</mo><mn>5</mn><mi>x</mi><msup><mo
stretchy="false">)</mo><mn>5</mn></msup></mrow><annotation
encoding="TeX">(2-3x)^3 (3-5x)^5</annotation></semantics></math><br>
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<div class="moz-signature">The term on the left would be negative if
x exceeded 2/3 (which is 0.6666). The term on the right would be
negative if x exceeded 3/5 (which is 0.6). I select whichever one
of these is the SMALLEST for my upper bound. <br>
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<div class="moz-signature">That should make sense, because if I
plugged 0.6666 into the term on the right it would be negative.<br>
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<div class="moz-signature"> </div>
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<div class="moz-signature">Does that help?<br>
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<div class="moz-signature">-- <br>
<b><i>Andrew J. Pounds, Ph.D.</i></b><br>
<i>Professor of Chemistry and Computer Science</i><br>
<i>Director of the Computational Science Program</i><br>
<i>Mercer University, Macon, GA 31207 (478) 301-5627</i></div>
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