[pure-silver] Re: Basic Chemistry

  • From: "mail1" <mail1@xxxxxxxxxxxxxxxxx>
  • To: <pure-silver@xxxxxxxxxxxxx>
  • Date: Sat, 14 Jun 2008 09:48:07 -0700

I found a Jobo Tempering Box which holds 6 1liter bottles and has a place
for my reel tanks. These units can be found on eBay for a reasonable price.

Jonathan

-----Original Message-----
From: pure-silver-bounce@xxxxxxxxxxxxx
[mailto:pure-silver-bounce@xxxxxxxxxxxxx] On Behalf Of Nicholas O. Lindan
Sent: Thursday, June 12, 2008 3:25 PM
To: pure-silver@xxxxxxxxxxxxx
Subject: [pure-silver] Re: Basic Chemistry

<eroustom@xxxxxxxxxxx>
> I use a hot bath to put my bottles of working 
> solutions in to bring them to temp. 

> If my solutions are all at basement temp of 
> 60 to 64F, what should the hot bath be at to 
> bring everything to 68-70F. 1 Liter glass 
> bottles (usually full). 6 Liter tub of water.

Well, in typical high-school chemistry fashion:

 Neglecting the thermal effects of the bottles
 Assuming everything is in a perfectly insulating container

 Aq + Br + Cs = T * (A + B + C)

 A, B, C ... are the volumes
 q, r, s ... are their initial temperatures
 T is the final temperature

Which should be sort of obvious, if you
think about it.

For a bottle (vol. A, temp q) in a water bath 
(vol. B, temp r), the temperature r at the start to 
reach a final temperature T should be

 r = [(A / B) * (T - q)] + T

or: r = [(the ratio of the volumes)
            times 
         (the difference in temperatures)]
            plus
         the final temperature 

Not a bad thing to tape to the wall.

For one bottle:

 The volume ratio is 1:6
 The temperature difference is 68F - 62F = 6F
 The final temperature is to be 68F

 r = 1/6 * 6F + 68F
   = 70F water bath

For 3 bottles the volume ratio is 3:6,
the student can calculate the temperature.
Quiz next Tuesday.

In real life things will be different: you have a flow of
heat to the air, the water bath container, the lab bench,
the glass bottle, and you are loosing heat to evaporation, 
gaining heat from your stirring, loosing heat to warming 
the chemicals in the bottle (don't forget to use the
volume of the water _before_ the chemicals were mixed in)...

Experiment and making a table will be the fastest and 
most accurate method.  Which is also sort of obvious.

==
Nicholas O. Lindan
Cleveland Engineering Design, LLC
Cleveland, Ohio 44121
============================================================================
=================================
To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you
subscribed,) and unsubscribe from there.

No virus found in this incoming message.
Checked by AVG. 
Version: 7.5.524 / Virus Database: 270.3.0/1499 - Release Date: 6/12/2008
7:13 AM
 

No virus found in this outgoing message.
Checked by AVG. 
Version: 7.5.524 / Virus Database: 270.3.0/1502 - Release Date: 6/13/2008
7:25 PM
 

=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your 
account (the same e-mail address and password you set-up when you subscribed,) 
and unsubscribe from there.

Other related posts: