http://koh.olinchloralkali.com/Techn...seDiagram.aspx
With a 28% mixture the freezing point is -65* C!
Your electrolyte will never freeze in your car unless you live in Antarctica.
BoyntonStu
Senior Member
Freezing point of KOH/H2O.
http://koh.olinchloralkali.com/Techn...seDiagram.aspx
With a 28% mixture the freezing point is -65* C!
Your electrolyte will never freeze in your car unless you live in Antarctica.
BoyntonStu
So now what can we put in the bubbler? another problem fixed
Super Moderator
Go to home depot and spend $10 on a gallon of denatured alcohol, this will keep your bubbler water from freezing at a 20% mix.Originally Posted by Gary Diamond
Hey Larry at the north pole, will this work
Senior Member
Russ,
Adding lemon juice or vinegar to the bubbler may also neutralize the KOH.
I am looking for a long lasting ph indicator to add to the solution.
Suggestions?
BoyntonStu
Super Moderator
Stu,
How about building one of these? Very cheap!
http://www.66pacific.com/ph/simplest_ph.aspx
Russ.
Senior Member
Russ,
You don't know me well enough if by cheap I would need to purchase:
This is a pH probe (or pH electrode). It's a Pinpoint brand electrode from American Marine, Inc., purchased from a mail-order pet supplier. It cost $45 in 2007. Note that the delicate glass bulb at the tip is still enclosed in the shipping cover, which protects it and keeps it wet. You can see that some of the salt in the buffer solution inside the shipping cover has creeped out at the edge of the cover. The cable is 10 feet (3 meters) long. The connector at the end is male BNC connector.
Cheap means boiling 50 cents worth of red cabbage in order to make a ph indicator. (Blueberries will also work but they are too expensive)
Overview:
Make your own acid/base indicator by boiling red cabbage. Use the juice to pH different fluids.
Equipment:
1. 1/2 head of *red* cabbage or so.
2. Metal grater.
3. Pot filled with enough water to cover the grated cabbage.
4. Strainer
5. Some acid/base solutions: for an acid try vinegar, for a base - mix some detergent in water.
Safety:
Be careful with the fingers when grating the cabbage.
How to do the experiment:
1. Grate the cabbage into small pieces and place them in the pot + water.
2. Boil the mixture for 20-30 minutes, until the liquid turns a dark purplish color.
3. Decant the fluid into a glass or jar, pouring through a strainer to remove the cabbage. Save the cabbage.. mix with a little vinegar and you can eat it on hot dogs, etc.. The collected fluid should be bluish/dark purple in color.
4. Make up some 'test' acid/base solutions. A good acid to use would be white vinegar. You could also try soda water/sprite or diluted juice from a lemon or orange. You can make a basic solution by mixing some washing detergent in water, or by adding some baking soda (sodium bicarbonate) to water. It's useful to have a control solution of (neutral) water - distilled water is best if you have access to it.
5. Add a few drops of the cabbage juice to your solutions, and note any color changes. The juice should turn pink in acidic solutions, and green in basic solutions.
6. You can use the indicator on any other solutions of interest, or try drying it on coffee filters to create a simple form of "pH paper."
Explanation:
Red cabbage contains pigments call anthocyanins. The pigments give it the red/purplish color. Anthocyanins belong to group of chemical compounds called flavonoids.
For most pH indicators, the compound acquires a proton at low pH (lots of H+) but looses it at higher pH. This seemingly minor alteration is sufficient to alter the wavelengths of light reflected by the compound, thus creating the color change with respect to pH. Anthocyanins behave somewhat inversely in that the pigments "gain" an -OH at basic pH, but loose it at acidic pH. The WWW link below describes the chemistry with structures if you want to see the details.
The chemistry behind pH, acids and bases.. An acidic solution contains an excess of protons or H+. pH is a measure of how 'acidic' a solution is. The lower the pH, the more acidic the solution. In chemical terms, pH means "the negative log of the concentration of protons" in solution. Chemistry students should recognize this as pH = -log[H+]. If the concentration of H+ is .01M, the pH will be:
-log[.01] = -log[10^-2] = -(-2) = 2 (very acidic!).
"Neutral" solutions (water, e.g.) have a pH of 7. This number coicides with the amount of H+ naturally formed in water from the equilibrium reaction: H2O <--> H+ + OH- (H+ experimentally known to be ~10^-7M; OH- is also the same concentration). "Basic" solutions have a pH greater than 7 - meaning they have less free H+ than that of neutral water.
KISS
BoyntonStu
Super Moderator
Stu,
LoL! You're so tight! Does your ass squeak when you walk? Do you set your alarm for 2am each morning so you can make sure you aren't losing any sleep?
LoL! Only joking!
How about $33? Cheap enough yet?
http://secure.sciencecompany.com/Han...16315C679.aspx
Russ.
Were do you get the prob?
http://cgi.ebay.com/HANNA-HI-981401N...ayphotohosting
Senior Member
Yes this works but you need a little more than 20% as it really gets cold.
Larry
Posting Permissions
Reply With Quote