Ugh, I live in Milwaukee right now and the tap water is HARD. I'm afraid to test for TDS. You can smell it coming out of the faucet.
How to lower PH without RO and tannins?
- Thread starter Icedcoldmine
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Ugh, I live in Milwaukee right now and the tap water is HARD. I'm afraid to test for TDS. You can smell it coming out of the faucet.
Milwaukee tap water averages 250ppm Total Hardness (considered medium hard), 7.8 pH, so what you smell is probably coming from the trap under the sink (not the water), but it may have a slight chloramine odor because that is what is used as a disinfectant.
I was able to have at least 50 species of cichlids, many live bearers, a few anabantids, and even some killifish spawn in minimally treated Milwaukee tap water (I only used a small amount Sodium Thiosulphate to neutralize chloramine from the tap)
I was able to have at least 50 species of cichlids, many live bearers, a few anabantids, and even some killifish spawn in minimally treated Milwaukee tap water (I only used a small amount Sodium Thiosulphate to neutralize chloramine from the tap)
pH = negative of the base 10 logarithm of the molar concentration
pH = -log[H+]
molar concentration = moles solute / liter solute
1 mol = 6.022 x 10^23 of something
molar concentration : how many moles of the thing in question (in this case H+) in one liter
so pH is a measure of how many moles of H+ are in a given amount of solvent (e.g water). The reason we use the negative logarithm is simply to make the numbers easier to deal with. Because its a negative logarithm, more H+ is a lower pH (eg 4), less H+ is a higher pH (e.g. 10).
The pH of pure water is about 7 because this is the amount of H+ that water produces by autoionization.
OK. Thank you.
So if [H+] = 1x10^-pH and [OH-] = 1x10^pOH and we know that pH+pOH=14 at 25C, then for a pH of 6, the ratio of [H+]/[OH-]=1x10^-pH/1x10^pOH=1x10^-6/1x10^-8=100.
Which means 100 H+ for every 1 OH-. But one can have the same pH of 6 and have 1000 H+ for every 10 OH- or 10,000 H+ for every 100OH-, meaning the pH remains the same although the actual number of ions can increase. So knowing just the pH, doesn't really give you any information of total number of ions and water with the same pH can act totally differently due to total number of ions.
If for example you add RO water, you will reduce conductivity, dGH and dKH but the pH won't change until the ratio between H+ and OH- changes, which will eventually happen the purer the water is. The "purer" the water the bigger the downward pH swings but one can also have a crashing pH due to acids in the water altering the ratio and not because their water becomes purer, as it is the case of adding RO water, but quite the contrary, it becomes "polluted". in which case although the pH goes down, the conductivity and dGH go up, quite the opposite of the case of adding RO water although you may achieve the exact same pH.
So again, you can't have a meaningful understanding of water quality by just measuring a pH value. And you can't have softer water by decreasing the pH value via any other means but diluting with RO water.
You may be able to explain it better to me by knowing chemistry inside out but empirical evidence points that's how it works.
What are you taking the ratio of [H+]/[OH-]? Where is this in the definition of pH?
What? This is the same ratio. You're just adding a zero at the end of both??
The total number of ions in solution is defined by something called ionic strength.
"Pure" water has a pH of 7 because of the ion dissociation constant of water (Kw). pH is one of the most fundamental characteristics of an aqueous solution along with temperature.
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I am just trying to demonstrate mathematically that the pH will remain the same regardless of the number of ions in the water as long as the ratio between H+ and OH- remains the same but the total number can change.
What does this have to do with the paragraph you quoted? Sorry about my bad way of expressing myself. By pure water I mean RO water , very low on minerals, which does not have a pH of 7, but a lot lower normally due to lack of dKH.. Water with a pH of 7 is where there is a balance between pH and pOH, where they are both 7. Their ratio the way I calculate it, is 1:1 - i.e. equal numbers of both ions in the water, or call it equal concentration or equilibrium.
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But the total number of ions is the same..? You understand that if you add a zero to both the denominator and the numerator in a ratio that nothing changes? The ratio is the same you have just un-simplified
Exactly! It is the ratio that doesn't change. However, the total number is not the same! The ratio between them only remains the same...
10,000 H+/10,000 OH- would produce the same pH of 7 as water with 100 H+/100 OH-.
So the total number is different, i.e 20,000 vs 200, but the pH is the same.
P.S. I am not adding zeros.....I am multiplying the numerator and denominator by the same number,which way the equation remains true, but it demonstrates that you can have the same pH but the total number of ions can change. As long as the ratio between them is the same, pH will remain the same.
In practice this is like comparing Old Tank syndrom tank with a crashed pH of 5 and an RO low mineral content tank with a pH of 5...for example.. Both have the same pH but the water properties are completely different.
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The total number is not different because it is not specified. You are only giving the relative amount of each. You can only have ONE pH for a given amount of H+. If you have 10,000 ions in solution for a given volume instead of 100 then the pH has to be different. Any time you add or take away H+ ions in solution the pH changes.
If you have 10,000 H+ instead of 100 H+ then the volume of solvent has to be 10 times bigger otherwise the pH is different. This is what is implied if you multiply the numerator and denominator by 10.
Not true, because H+ and OH- and the formula used to calculate them, are interrelated. When the balance between them is the same, the pH is the same. Basically the concentration of them both can be larger or smaller but as long as the concentration is in the same ratio, pH remains the same.
I agree that if you swing just the H+ but not the OH-, the pH will change., and so will the pOH, in the opposite direction. The pH or pOH only remains the same when the balance between the two is the same, i.e. the ratio.
