Stands for Potential of Hydrogen and is a measure of how acidic or basic an aqueous solution is.

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Can an acid or base have a pH less than 0 or more than 14? [duplicate]

This question has been asked earlier, but I could not understand it. Please, someone explain it in an easier way.
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Mix 1M Tris/HCl pH 7.5 and 1M Tris/HCl pH 9.5 to get pH 8

most of the question is already in the title. I have two pre-made buffer solutions: 1M Tris/HCl with a pH of 7.5, and 1M Tris/HCl with a pH of 9.5. What I need is a 1M Tris/HCl buffer with a pH of 8. ...
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44 views

Does a weak buffer solution still maintain a mostly steady pH if the acid or base load it has to buffer is small?

I need to buffer the $\mathrm{pH}$ of a solution to $3.0$ using a citrate buffer. I found a recipe to make a buffer solution that would use $82\%$ of $0.1\,\mathrm M$ citric acid (monohydrate) and ...
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15 views

Buffer capacity in a solution [closed]

Buffer capacity is a measure of a buffer solution\'s resistance to changes in pH as strong acid or base is added. Suppose that you have 145 mL of a buffer that is 0.220 M in both formic acid (HCOOH) ...
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53 views

pH 10 to pH9 NaOH dilution

I have a pH 10 NaOH solution. I need to bring down the pH to 9. So I used the $C_1V_1 = C_2V_2$ approach. $C_1 = \mathrm{0.0001~mol/L}$ $V1$ is the necessary amount to produce 10 L of pH9 $C_2 ...
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31 views

net charge nucleobases at alkaline conditions

While doing anion exchange chromatography of short oligonucleotide, I have noticed that at $\rm pH=12$, the oligo- retains longer on the column than the same oligo- at $\rm pH=8$. I thought the reason ...
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41 views

Find the concentration of the HCl solution when mixed with 1.265g of ACES-K+

$1.265\ \mathrm g$ of N-(2-acetamido)-2-aminoethanesulfonic acid potassium salt (ACES-K+, $M=220.29\ \mathrm{g/mol}$) is dissolved in $88.42\ \mathrm{mL}$ of water. $27.59\ \mathrm{mL}$ of ...
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exchanging H2O in buffer for D2O - pH vs pD?

I have TBS pH 7.4 buffer that I am exchanging all the water out for D2O. How do I find out what the pD is after all the water is gone? I understand that pH meters don't work for deuterium, and it ...
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17 views

How to calculate pH of strong base and weak acid flows in a reactor?

I have a bubble column and I would like to calculate the pH that follows, when I have two fluids with different volumetric flow rates coming into the reactor (one is a weak acid an the other is NaOH). ...
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8 views

pH, conc vs activity

After studying a somewhat overview of "gamma" activity coefficient (it is not actually in our course but may come in exam as a part of unknown paragraph in ionic equilibrium) I can understand most ...
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1answer
34 views

Charge of an amino acid sequence

I have the following problem: A polypeptide has the following sequence (amino end on the left) $$\mathbf{lysine - aspartic~acid-histidine-arginine-serine}$$ Using the $pK_a$ information ...
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1answer
33 views

Why does the acetyl group drop the pH? [closed]

I have a molecule that is 8% of the R groups are replaced with Acetyl groups. When I dissolve it in water it drops the pH. I am trying to understand why.
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21 views

pH-dependency of the acidic dissociation of carbonic acid

I know the product of $\ce{CO2 +H2O}$ yields $\ce{H2CO3}$. This is a reversible equation so $\ce{H2CO3}$ goes back to $\ce{H2O + CO2}$. However, my question is: Is there a certain pH which will ...
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1answer
48 views

Composition and pH of water produced by air conditioners

I would like to know if there are specific studies or research regarding the condensed water that is generated by air conditioners. Many people feel that this water is acid and corrosive but could ...
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2answers
40 views

Can I use lye as a cooking leavener instead of baking soda?

I asked this question on the cooking site, but got unsatisfactory answers: http://cooking.stackexchange.com/questions/65520/can-i-use-lye-as-a-leavener-instead-of-baking-soda I'm interested to try to ...
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64 views

How many grams of MnS will be produced?

1 L of a solution (conc.: $\rm 2\times 10^{-3}~M$ of $\ce{MnCl2}$ buffered with $\rm pH=6$ is saturated with 2.5 L of gaseous $\ce{H2S}$ in standard condition. The final volume is 1 L. How many ...
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1answer
55 views

Fluctuation in pH reading on pH meter

I was conducting a titration of a saturated $\ce{Ca(OH)_2}$ solution against $\ce{HCl}$ using a pH meter (the kind with a glass electrode). At the beginning of the titration, the pH reading would drop ...
3
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60 views

Understanding how to calculate the pH of a buffer with ice tables

Let's say you are asked to calculate the pH of a solution with: $\mathrm{0.1~M}~\ce{HCl}$ $\mathrm{0.2~M}~\ce{CH3COOH}$. $\mathrm{K_a = 2.10^{-5}}$ This is how I would do it: $$\ce{CH3COOH + ...
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34 views

Ph= PKa in a titration of a strong acid with a strong base (or vice versa)

Generaly during the titration of a weak acid/base with a strong base/acid, we can directly read the pKa of the titrand couple which corresponds to the value of half the equivalence volume of the ...
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65 views

Why does CO2 lowers the pH of water below 7?

Ok so I understand that having a pH below 7 is considered to be acidic and I also understand that part of the definition of an acid is that it gives off H+ when dissolved in water(even though not all ...
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26 views

Mechanism of pseudo buffer pH maintenance

Some solutions, like concentrated HCl, act as buffers even though they lack the buffering component. What is the cause for such a behaviour?
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50 views

Is there a relationship between pH indicator colors and the visible light spectrum?

When I examined the colors showed on a pH paper which is red for acids and violet for bases, greenish yellow for neutral and other ranges in between, I noticed that the sequence is exactly same to ...
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1answer
69 views

Experimental determination of pKa

I have $20~\mathrm{cm^3}$ of a $0.1\ \mathrm{M}$ ethanoic acid solution and have to find out the $\mathrm{p}K_\mathrm{a}$. In experiment this solution had a $\mathrm{pH}$ of $2.91$. Do I use the ...
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73 views

Determining the nature of common pH indicators (methyl orange) using Le Chatlier's principle

I got some good information about this topic yesterday, and I understood what I was told, but I have come up with a specific way of phrasing the problem I'm having. It is slightly different than ...
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43 views

Why is the ionic product for water $10^{-14}$? [closed]

Why is the reference value of $K_w=10^{-14}\ \mathrm{M}^2$, such that $[\ce{H+}]= 10^{-7}\ \mathrm{M}$ and $[\ce{OH^-}]= 10^{-7}\ \mathrm{M}$ for pure water at $20\ ^\circ \mathrm{C}$? For example, ...
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102 views

How to find out pH of aquarium and apply it when adding HCl?

I'm trying to rescue a neglected fish tank. I've been trying to figure out how much extra hydrochloric acid to add to my water change for my fish tank to soften the water a little and reduce the pH a ...
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42 views

How do we know concentration of H+ is 10^-7 while deriving Kw , ion product of water?

How do we know concentration of $\ce{H+}$ is $10^{-7}$ while deriving $K_w$ , ion product of water? We say [$\ce{H+}$][$\ce{OH-}$]=$K_w$ , then we substitute [$\ce{H+}$]=[$\ce{OH-}$]= $10^{-7}$ . ...
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1answer
40 views

Buffer Systems and Ion Reaction

If we have a buffer solution as follows where HA is a weak acid and $\ce{A-}$ is its conjugate base, $\ce{HA + H2O<=>H3O+ + A-}$, do we ever consider $\ce{A- + H2O<=>HA + OH-}$? This is ...
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255 views

MgCl2 acidic or neutral in water?

I'm currently taking chemistry 12. On our test we were asked, when given a $0.1~\mathrm{M}$ solution of certain compounds whether the resulting solution when added to water would be acidic, basic, or ...
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28 views

Is there a formula for calculating pH deviation? [closed]

What is the general formula for mixing water with different pH levels? I'm going to use it as part of the algorithm in our programming class that would be used for pH correction.
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92 views

Will a strong acid still dissociate “completely” even in the presence of a stronger acid?

For example, nitric acid or sulfuric acid in an equal-molar solution of perchloric acid. Won't perchloric protonate a significant concentration of nitrate ions?
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How does the amino acid profile of Greek yogurt change over its lifespan [closed]

i would like to measure the change in lysine quantitatively over the lifespan of greek yogurt. how can i do that experimentally.
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1answer
39 views

link between acidity and [H3O+]

Suppose I have an aqueous solution (1) of $\ce{CH3COOH}$. The chemical species in the solution will be $\ce{H2O, H3O+, CH3COO-}$ and, since it's a weak acid, some $\ce{CH3COOH}$ will remain. Suppose ...
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Confusion regarding pH calculation [closed]

How do I calculate pH of dilute concentration like 10-8 M HCl? Is it different in the way I should find out pH of 10-3 M HCl's pH
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1answer
30 views

pH adjustment within effluent

We have an effluent tank, with a consent to discharge at between 5.5 - 11pH, the tank holds 100,000litres of dirty water. When the pH reaches 10.5 we add citric acid to bring the pH down. How many ...
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118 views

Effect of PH of medium on ionization of weak acids/bases

As the title says , what is the effect of PH of the solution on the ionization of weak acid like acetic acid or weak base. Will the degree of ionization of acetic acid increase in higher PH value? ...
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Predictions about hydrolysis reactions [duplicate]

Predict whether these $1.0~\mathrm{M}$ solutions are acidic, basic, or neutral. Lets start with $\ce{CH3NH3+NO3-}$ How do I approach a problem such as this? I certainly do not know all the chemical ...
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33 views

Solubility of salts of weak acids in lower pH

I know that the solubility of salts of weak acids increases in lower pH , but is there a mathematical proof to support this statement ?
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53 views

Generally at what pH will an acid ionise/lose a proton and why? [closed]

In paired-ion chromatography you need to carry out the process under a pH where your analyte of interest will ionise, e.g. if its an acid it needs to deprotonate. but I'm not that sure how you would ...
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3answers
93 views

Solubility Product and Buffers

I've been assigned a homework and the question looks like this :- The ionization constant of benzoic acid is $6.46 \times 10^{-5}$ and solubility product for silver benzoate is $2.5 \times ...
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1answer
72 views

calculate the pH of a solution that is 0.0400 M in disodium hydrogen arsenate [closed]

I tried to read my text book(skoog) but I fell a bit behind in my classes and am lost as to where to look. To be honest, if anyone could solve step by step, a similar or this problem I would be very ...
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1answer
22 views

pH of a mixture of base and an acid

I have the following question: Assume that you have two solutions. One of $50\ \mathrm{cm^3}$ $\ce{HCl}$ $\mathrm{pH} = 1.3$ and one of $150\ \mathrm{cm^3}$ $\ce{Ba(OH)2}$ $\mathrm{pH} = 12.3$. If we ...
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71 views

Titration curve of a diprotic acid with a strong base titrant

I have wonders regarding the titration curve of the titration of sulphuric acid, or any diprotic acid, with a strong base. I am aware of the fact that a diprotic acid is protolysed in two steps but, ...
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1answer
65 views

Acidic and alkaline salt solutions: why do some salt form acid/bases while others don't

I have a question regarding salts and their solutions. How come some salts, like sodium carbonate and ammonium chloride, produce acids/bases when dissolved in water? Moreover, how can you predict ...
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pH level of fabric with regard to inhibiting fungal growth

Someone on another forum made the point that doing laundry with sodium hypochlorite (bleach) will kill any fungus such as athlete's foot fungus, but that after the fabric dries, the pH level of the ...
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61 views

Phosphate buffer system

Can anyone show me how to find the masses of $\ce{NaH2PO4}$ and $\ce{Na2HPO4}$ needed to prepare $1.0~\mathrm{L}$ of a $0.1~\mathrm{M}$ phosphate buffer solution with $\mathrm{pH} = 7.4$ using the ...
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385 views

Effect of Temperature on pH of Water

The $K_\mathrm w$ is a function of temperature. It is $10^{-14}$ at $25\ \mathrm{^\circ C}$. When the temperature is $50\ \mathrm{^\circ C}$, the $K_\mathrm w$ can be calculated to be somewhere ...
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56 views

Why does pH cause a change in the color of indicator solutions?

Why does pH actually cause an indicator to change in color? Obviously different indicators change colors at different pH's, as seen on the following page: https://en.wikipedia.org/wiki/PH_indicator ...
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1answer
258 views

Calculating pH of a NaCH3COO solution [closed]

A practice question I am working on is as follows, What is the pH of a 0.397 M aqueous solution of $\ce{CH3COONa}$? $\mathrm{K_a (\ce{CH3COOH}) = 1.8\times10^{-5}}$ We have worked thus far on ...
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What is the physical quantity/magnitude of pH?

I have a database to classify variables/parameters in water resources as follows: Variable: Precipitation (P); Quantity: Length; Units of measurement: mm (millimeters). Following the example, what ...