topic Calculation of mixture amounts in Mathcad

Calculation of mixture amounts

azikorus-disabl — Thu, 03 May 2018 23:17:00 GMT

Collab,This is probably a simple calculation for a chemist, however, I am a bit baffled. The mix, as it were, will be Component A plus 3 solvents:Component A is a dispersion of silicone, 50% by weight, specific gravity = 0.861Component B is a solvent, specific gravity = 0.712,

Calculation of mixture amounts

ptc-1368288 — Mon, 11 Sep 2006 07:00:00 GMT

Art,

There are lots and lots of chemicals sheets in the web.
at least visit Mike griffin.

jmG

Calculation of mixture amounts

StuartBruff — Mon, 11 Sep 2006 07:00:00 GMT

On 9/11/2006 6:00:46 PM, ArtZ wrote:
== This is probably a simple calculation for a chemist, however, I am a bit baffled. The mix, as it were, will be Component A plus 3 solvents:
== Component A is a dispersion of silicone, 50% by weight, specific gravity = 0.861
== Component B is a solvent, specific gravity = 0.712, 34% w/w of the mix
== Component C is a solvent, specific gravity = 0.78, 35% w/w of the mix
== Component D is a solvent, specific gravity = 0.79, % adjusted to get final dispersement % of Component A
== The question is: How to mix using volume measure to obtain a 2% (w/w) dispersion of Component A in 10 ml total volume of mix?

Being even more baffled and not understanding the significance of the silicone dispersion "50% by weight", does the attached hold any clues?

Stuart

Calculation of mixture amounts

azikorus-disabl — Tue, 12 Sep 2006 07:00:00 GMT

Stuart,

Thanks for your reply. The significance of "Component A is a dispersion of silicone, 50% by weight," just simply means that the available solute is 50% available.

With this in mind, for a 2% yield of component A (the solute), the "percentage weights in mix" as you called it, would change from 2% for wA to 4%.

Otherwise, seems your calculation is spot on. It's interesting that in reality, the problem is quite simple, yet I and several others made it out to be more complex than it is.

Thanks for the reality check.

Art

Calculation of mixture amounts

ptc-1368288 — Tue, 12 Sep 2006 07:00:00 GMT

On 9/12/2006 12:00:58 AM, ArtZ wrote:
>Stuart,
...
>yet I and several others made
>it out to be more complex than
>it is.
>
>Thanks for the reality check.
>
>Art
___________________

Art,

You should be able to define an objective function and a criteria function depending upon the objective function ... then Minimize the criteria function.
Thus, you will have a simple logical approach that will suit up to 200 components (?), in an elegant simple steps.

jmG

Calculation of mixture amounts

ValeryOchkov — Tue, 12 Sep 2006 07:00:00 GMT

If (��) you (��/��) know (��) Russian (��) you (��/��) can (��) to solve (��) one (��) mixture amounts task (�� ) on the MAS (� ��):
(Change View/Coding/Cyrillic)
http://twt.mpei.ac.ru/MAS/Worksheets/Chem/Chem_R_N26t.mcd

Val
http://twt.mpei.ac.ru/ochkov/v_ochkov.htm

Calculation of mixture amounts

StuartBruff — Wed, 13 Sep 2006 07:00:00 GMT

On 9/12/2006 12:00:58 AM, ArtZ wrote:
== Otherwise, seems your calculation is spot on. It's interesting that in reality, the problem is quite simple, yet I and several others made it out to be more complex than it is.

IME, that's QED - quite easily done 😕

== Thanks for the reality check

No worries, Art. Glad I wasn't drawing my reality check on the bank of Goodyear 🙂

Stuart

Calculation of mixture amounts

ptc-1368288 — Wed, 13 Sep 2006 07:00:00 GMT

On 9/13/2006 7:07:57 AM, stuartafbruff wrote:
>On 9/12/2006 12:00:58 AM, ArtZ wrote:
>== Otherwise, seems your calculation is
>spot on. It's interesting that in
>reality, the problem is quite simple,
>yet I and several others made it out to
>be more complex than it is.
>
>IME, that's QED - quite easily done 😕
>
>== Thanks for the reality check
>
>No worries, Art. Glad I wasn't drawing
>my reality check on the bank of Goodyear
>:-)
>
>Stuart
_______________________

Stuart.

Can't you draw a reality check from your "Minimize Bank" . I mean restate the problem in a general stoichiometric form that could be used universally . I mean zap these w/w ... just figuring that in Engineering work we use "Mass" .
In my view, that example from Art is for a poison recipe. Once done in mass, no problem to convert back to individual volumes !

The wording of that problem gave the flue !

jmG

Calculation of mixture amounts

StuartBruff — Wed, 13 Sep 2006 07:00:00 GMT

On 9/13/2006 9:03:42 AM, jmG wrote:
== Can't you draw a reality check from your "Minimize Bank" . I mean restate the problem in a general stoichiometric form that could be used universally .

What? I want out. I went too far too soon. I didn't know what I was gettin' into. I didn't know you had to follow a good idea with loads more little good ideas.

== I mean zap these w/w ... just figuring that in Engineering work we use "Mass" . In my view, that example from Art is for a poison recipe. Once done in mass, no problem to convert back to individual volumes !

If it's a poison, Art's obviously doing Chemistry (or Domestic Science) not Engineering.

Art's problem is quite specific. I imagine that part of the problem is the volume constraint and the quantification system used for the solutions; hence writing it in terms of mass might not be helpful for the give problem domain.

It's fairly easy (using the vector approach) to write a function to solve for Art's required volume and concentration. I don't know what the specification of the more general problem is that you have in mind.

== The wording of that problem gave the flue !

Smoke gets in your eyes,
When you Minimize ...

Stuart

Calculation of mixture amounts

azikorus-disabl — Wed, 13 Sep 2006 07:00:00 GMT

Hey all,

Didn't we learn about the KISS principle? And, as we ask often at work: "How many Ph.D's does it take to screw in a light bulb?"

Art

Calculation of mixture amounts

ptc-1368288 — Wed, 13 Sep 2006 07:00:00 GMT

On 9/13/2006 10:27:51 PM, ArtZ wrote:
>Hey all,
>
>Didn't we learn about the KISS
>principle? And, as we ask
>often at work: "How many
>Ph.D's does it take to screw
>in a light bulb?"
>
>Art
_______________________

Can you rewrite it in understandable format ?

jmG

Calculation of mixture amounts

azikorus-disabl — Wed, 13 Sep 2006 07:00:00 GMT

Jean,

I am not quite sure what you are asking? Stuart's response to my question was certainly adequate for my needs. What else would he (we)do?

Art

Calculation of mixture amounts

azikorus-disabl — Wed, 13 Sep 2006 07:00:00 GMT

Jean,

If I only have four, why do I need 200?

Art

Calculation of mixture amounts

ptc-1368288 — Thu, 14 Sep 2006 07:00:00 GMT

On 9/13/2006 11:06:57 PM, ArtZ wrote:
>Jean,
>
>If I only have four, why do I
>need 200?
>
>Art
__________________

Well ! ... my 200 is like the fish, "that long" !
Make up to 10 (for instance

jmG

Calculation of mixture amounts

ptc-1368288 — Thu, 14 Sep 2006 07:00:00 GMT

On 9/13/2006 10:42:05 PM, ArtZ wrote:
>Jean,
>
>I am not quite sure what you
>are asking? Stuart's response
>to my question was certainly
>adequate for my needs. What
>else would he (we)do?
>
>Art
___________________________

Presumably it means solving n equations in n unknowns .
The problem is understanding the stoichiometric setup.

Jean