Acidic waters and CO2 buffers

[ADR]

I have been following the threads on lemon juice, citic acid, bicarb and buffers and have been dabbling a bit with body pH. Last night I tested the pH of our tap water which was 7.6 - no surprise there and also tested our local bottled water (spring water) which was 5.2 (quite acidic :duh )

According to the bottle the typical contents include (mg/L):
- bicarbonate -> 5
- sodium -> 11
- chloride -> 20
- calcium -> 1
- magnesium -> 4.7
- potassium -> 0.5

My question is what is the result of digesting this in relation to buffers and is this similar to citrus drinks. ie acidic but make you alkaline through digestion?

 

[efattah]

The acid/base balance of your water is not just determined by mineral content, but also by the ionic state of the water. Negatively ionized water tends to be more alkaline, while positively ionized water tends to be more acidic (called hard water).

I don't think that drinking acidic water will make you more alkaline, unless there is an actual acid in the water. It is the neutralization of acids (i.e. citric acid, phosphoric acid), which can alkalize your body during & after digestion.

In the case of your spring water, I doubt there is any real acid in it, so the pH may be caused by positive ions, or perhaps plastic-based chemicals leaching from the plastic into the bottle.

 

[ramstam]

I think that there are so many weak acids and bases working with our basic(meaning simple not pH) H2CO3 blood balancing act that it is difficult and very dangerous to try to play with it. I tried to build an equation to show most of the acid/base reactions and it was a disaster.

 

[ADR]

don't we "play with it" every time we eat or drink something?

 

[ramstam]

Yes, eating/drinking/breathing all change the pH. I am talking about tring to overcome all the buffers with a food or drink or something. As we get close to changing our pH the rate of change gets faster and I'm not sure we can control it, since we are not just big sacks of water. An example is NaHCO3, baking soda may be an easy thing to use, but do the increased Na+ ions change the way our muscles work? There are people doing incredible things in freediving. I have alot of work to do to catch up. Mostly they make me feel safe, if they can not have brain damage after 9min!! then I feel safe pushing to 6.

Eric, sounds like you have a solid chemistry background?

 

[Ocean Girl]

don't we "play with it" every time we eat or drink something?

oh dear.... :ban

 

[marginatus]

the blood's pH is around 7.40 and is kept constant by several buffer systems being the most important the HCO-3/H2CO2. pH variations would be very bad if not deadly

(sorry for my bad spelling but when it comes to technical sttuf it's a bit harder )

dive safe

Fernando

 

[naiad]

pH variations would be very bad if not deadly

The blood pH does change during apnea (higher after hyperventilation and lower due to CO2 accumulation). I don't know how much it changes by, but I think it is significant.

 

[cebaztian]

I once had the opportunity to be "measured" during a maximum breathhold.

http://www.fridykning.se/freediving/features/7min.html

PH read like this.

30 min before: 7.49
Just before:7.67
Just after:7.43

Does not seem to vary that much - or maybe I am abnormal - or maybe 0.2 is a big difference?

Sebastian
Sweden

 

[marginatus]

thanks for the correction.
from Sebastian's data the variation (using 7.43 and 7.67) on the concentration of HCO-3 would be 1.57739E-8 (pH=-log[]). I don't know what would be a big or small variation and the capacity of the buffers to compensate the CO2 variation. i'll try to get more info.

Fernando

 

[ramstam]

Instead of messing with the H3O+ in terms of pH I believe an easier way would be as a %. .23 =~a 23% increase in free protons. Since 1pH=10X more.

I wonder if we are even talking about the original question?

I guess Ocean Girl didn't spot that quote about being "measured".

ADR asked"My question is what is the result of digesting this in relation to buffers and is this similar to citrus drinks. ie acidic but make you alkaline through digestion?"

ADR, I think you are looking for the action of something called the
conjugate base of a weak acid.

 

[Ocean Girl]

I guess Ocean Girl didn't spot that quote about being "measured".

missed it! so how big was it? :girlie

 

[octopus]

30 min before: 7.49
Just before:7.67
Just after:7.43

..........

 

[Ocean Girl]

..........

wow!
rofl rofl

 

[octopus]

For Pete's sake...I only quoted cebaztian...scroll up.
And...I am not saying a word anymore. :mute