Ph Definition and 520 Threads

Hello there, During an experiment I had for my MSc Thesis for ammonia extraction, I used WWTP sludge and biogas digestate with an evaporation/distillation unit. I tried different combinations of sample vol. and evaporating flask vol. and then I added vacuum pressure. At first pH was dropping...

Although the masses of a mole of H+ and a mole of OH- are different, what is the number of ions contained in each?

Homework Statement The pair Ni2+/Ni has E°=-0.25V. Find the minimum pH of the sulution so that a nickel bar immersed in it, doesn't produce hydrogen. Homework Equations - The Attempt at a Solution This problem doesn't make any sense to me. Maybe there is a cell in which the following reaction...

Hi, I have been performing an experiment to determine whether there is any correlation between pH and the rate of electrolysis. I have performed it using monobasic, dibasic and tribasic acids of constant concentration. However, I can't seem to find any correlation. Is there something I should...

Homework Statement A 0.551 L solution of 1.37 M sulfurous acid (Ka1 = 1.5e-2 and Ka2 = 1.0e-7) is titrated with 1.65 M NaOH. What will the pH of the solution be when 0.7549 L of the NaOH has been added? The answer is 7.27. Homework Equations -log(H+)=pH pH = pKa + log(salt/acid) The Attempt...

We know pH is measured by the negative logarithm of concentration of Hydrogen ion. But what if the concentration in HCl is 10-9M then the pH will be 9. But how can it be possible since a pH of 9 is basic while HCl is an acid?

You prepare 0.5 liters of a solution by adding 0.75 moles of a weak acid HA to water. For HA, Ka = 10^-1 Finally you dilute this solution to a final volume of 2.0 liters. What is the pH of the diluted solution? My solution is this. [HA] = .75 mol /.5 L = 1.5 M. HA + H2O -> H3O+ + A-. If x...

Hello! I have a question concerning the functioning of a pH meter. All the sources online that I can find either omit, I think, important information, or describe it in "technical terms" with equations. I would like to know what is happening at the level of the distribution and movement of...

Hi. I would like to ask help on what is the equivalent of % w/v to pH? Say for example: What is the pH of 4% w/v?

Homework Statement To which of the following would the addition of an equal volume of 0.60 M NaOH lead to a solution having a lower pH? (a) water, (b) 0.30 M HCl, (c) 0.70 M KOH, (d) 0.40 M NaNO3. 2.The attempt at a solution the correct answer is 0.70 M KOH, and they say that by adding more OH...

Ka values of the 1st and 2nd dissociation of phthalic acid (HO2C-C6H4-CO2H) are given below. Estimate the pH value for highest buffer capacity when a buffer is prepared from 1:1 mixture of phthalic acid and sodium hydrogen phthalate (HO2CC6H4- CO2Na) in water? HO2C-C6H4-CO2H <=> H+...

Hello! Can anyone recommend a good guide 34 and NIST traceable pH buffer vendor. Our experience with our current vendor has left a bit to be desired, and we need a large variety of standards that limits our supply. Thank you for reading this and any help you may offer.

Homework Statement Prepare a buffer solution of pH 3.746 from 25 mL of 0.244 M weak acid with pka 3.54 What volume, in mL, of 0.275 M NaOH would need to be added? I think that I have the answer but I am not sure, could you look over the working to check? Also, would you do this differently...

Homework Statement The dissociation constant Ka for the acid-base reaction HA-->(H+)+(A-) is given by Ka = products / reactants; but instead of listing Ka, people generally list pKa = -logKa (where log indicates the 10-base logarithm). Similarly, instead of using [H+], people generally use pH...

Homework Statement A 50.0 mL sample of a 1.00 M solution of a diprotic acid H2A (Ka1 = 1.0 × 10–6 and Ka2 = 1.0 × 10–10) is titrated with 2.00 M NaOH. What is the minimum volume of 2.00 M NaOH needed to reach a pH of 10.00? (A) 12.5 mL (B) 37.5 mL (C) 25.0 mL (D) 50.0 mL Homework Equations...

Homework Statement A voltaic cell utilises the following reaction: 4 Fe2+(aq) + O2(g) + 4 H+(aq) ---> 4 Fe3+(aq) + 2 H2O(l) What is the emf of this cell when [Fe2+] = 1.3 M, [Fe3+] = 0.010 M, PO2 = 0.51 bar and the pH of the solution in the cathode is 3.5. The standard reduction potentials...

I'm considering of getting a Ph.D. abroad, but I have a dependent (my mother) who needs someone to look after her. Are there schools that offer Ph. D. scholarship and would allow me to bring my mom? I asked everyone around and they say it would be really difficult, if not impossible. Thank you.

Homework Statement What will the pH be by adding 1M HCL and 1M NaOH to pure water? Homework Equations pH= -log[H+] The Attempt at a Solution Well, If we form the reaction formula we get HCl + NaOH ---> H20 + NaCl This is a neutralizing reaction, so the net effect produces just water...

Why does tap water ph rise or decline after it has been set aside for a period of time. I've heard that Co2 or chlorine 'gas off' and the result in loss if CO2 can raise ph?

I recently read an article that a buffer that increases alkalinity to achieve a desired ph has it's in preferred ph value. For example, sodium bicarbonate holds water at a ph of 8.4. The article also went on to state that buffers don't always raise ph they can lower it too. The article...

Does temperature have an effect on the ph level? Does it depend on the type of acid? I'm just using water as an example. Thanks

How do I work out how many times more acidic a ph value of 6.8 is compared to 8.6? For example.

1. 0.250 M of NH4Br 2. Ka for NH4 = 5.52 x 10-10 and Kb for NH3 = 1.81 x 10-5 3. So I broke the salt down into its constituents and considering Br is neutral and NH4 is an acid, NH4Br is acidic. I am just confused with how to calculate the pH. I thought that I should do this...NH4 +...

I was reading this website (http://www.chembuddy.com/?left=pH-calculation&right=pH-amphiprotic-salt) on calculating pH of amphiprotic salts. My question is why can't you do something similar for diprotic acids? Take for example the diprotic acid H2S. Because you have the following...

I need to test the ph of river. I need a method of making an indicator that I can make at home. Please help !

Homework Statement Find the pH of 0.02025 M tartaric acid using the method of multiple equilibria given that its Ka1 value is 9.2*10-4 and its Ka2 value is 4.31*10-5. Homework Equations Kaoverall = Ka1 * Ka2 The Attempt at a Solution Please check the Word document. Is my method...

Hi, I am looking for some guidance for calculating the amount of H2SO4 required to reduce the pH of a Reactor outlet stream from 8.7 to somewhere in the 1.5-2.0 region. The stream contains a number of components in varying amounts such as C8H8O2, NaOH, H2O, Na2HPO4, NaH2PO4, C8H12N2O3S and...

Homework Statement Why is this true? Why is it that the reduction of oxygen is more favored in acidic solution rather than in basic solution? Homework Equations Acids are proton donors. The Attempt at a Solution Does this have anything to do with the fact that the...

For b), do I really need to look at the graph to get the volume of HCl poured? Is there not a more precise way?

Quick pH calculation -- Please verify A 50.0 mL aqueous solution of sodium hydroxide has a pH of 12.50. If 36.00 ml of 0.0200 mol/L sulfuric acid is added to this sodium hydroxide solution, what will be the new pH of the resulting solution? Assume that the temperature stays constant at 25C, and...

Hello Forum :), Please find attached my problem. The solutions is also there. BUT, I do not understand why my teacher does not simply assume pH=0. It seems as though we are using the standard hydrogen electrode (ie 1M H+ in solution!).

Homework Statement Calculate the pH of a solution containing 5.0 g of NaHCo_3 (molar mass = 84.0 g) in 250. mL of H20. NaHCO_3 is amphiprotic. k_a= 4.7x10^{-11}, k_b=2.3x10^{-8} This is for a General Chemistry II class, for the record. The Attempt at a Solution I started...

Homework Statement http://i.minus.com/jfUXIXvQJw8hw.png Homework Equations Ka of hydrogen sulfate ion will be taken as 1.2x10-2. Ka of ammonium ion will be taken as 5.6x10-10 Kb of ammonia will be taken as 1.8x10-5 Kb of sulfate ion will be taken as something very tiny (Kw/Ka of...

Homework Statement 20.0 mL of .200 M hydrochloric acid are mixed with 20.0 mL of .300M ammonium hydroxide. What is the pH? Also says that if ammonium hydroxide is in excess it immediately breaks down into ammonia and water. The Attempt at a Solution I know the NH4OH is in excess, there...

Hello, So as the end of the year comes to an end, AP Chemistry is getting increasingly more difficult to the point where I don't understand anymore. In our homework there is a questions asking to calculate the pH of a buffered solution. The only information it gives you is the chemical formula...

I am designing a surgical instrument which will be impacted many times over its life cycle. We are trying to determine the best heat treating option for the steel (17-4 precipitation hardened) so that we maximize its usable life. Typically, we heat treat 17-4 to H900. However, I'm not sure...

What can a PH meter tell you about the quality of fluid it is measuring?

What amount of sodium Nitrate must be added to 500 ml of .200 M solution of HN02. Ka=4.0^-4 Ka=(H+)(A-) -------- (HA) Ph of 5 = 1.0^-5 (H+) so, (1.0^-5)(x) ---------- = 4.0^-4 , however X turns out to be way too big...

OK folks, first of all, let me thank those of you who have helped me with previous questions... perhaps this is why I keep coming back! This time, I'm just asking those of you who are better than I am at this if I did this right and thus, got the correct result. I think I did, but since...

Hello everyone, I'm really confused. Here is a equation CO2 + H20 <----> H2CO3 <-----> H+ + HCO3- * Now if I increase carbon dioxide I know both both Hydrogen and bicarbonate acid increases 1. Why does this make it more acidic. The thing is what I'm thinking is if a solution...

Homework Statement Draw the structure of aspartic acid at PH 4. I calculated the PI and based on that, drew the charged structure. If anyone can confirm that this is the correct structure. Homework Equations The Attempt at a Solution I attached the structure. Thanks for any assistance.

Homework Statement Find the pH of 0.20 M Iron (III) sulfate. Homework Equations The metal ion becomes hydrated (water is a ligand) and forms iron hexahydrate. The sulfate ion is a weak base. The Attempt at a Solution Now, in considering the pH of this solution, should I consider the...

What is the pH when 200 mL 0.1 M NaOH is mixed with 300 mL water? I am stuck here. I know V1C1 = V2C2 but I need help at this point. I don't know how NaOH reacts with water, and how this would affect the pH of the final solution. I also don't know whether or not I should use the...

So I was thinking the other day why is kmph appear bigger than mph in conversions. I thought sense km was a bigger number it would be smaller because converting mi to KM u would reach .6 of a mile. Anyways I then I realized per hour is the rate at which it takes to travel that distant. So if i...

Homework Statement You mix the below two solutions. What is the resulting pH? 200 mL solution with H_{3}O^{+} = 1 * 10^{-4} 100 mL solution with H_{3}O^{+} = 2 * 10^{-11} Homework Equations pH = -log[H_{3}O^{+}] N_{H_{3}O^{+}} = M * L The Attempt at a Solution I first found the number...

\:Homework Statement What is the pH when 10 ml of 0.1 M NaOH is added to 25 ml of 0.1 M H_{}C_{2}H_{3}O_{2}? Homework Equations pH = -log[H_{3}O] The Attempt at a Solution The main thing confusing me about this type of problem is that my teacher taught me a way which is different from the...

Homework Statement Consider mixing a 100 mL solution of 0.1 M sodium sulfide with a 200 mL solution of 0.05 M hydrochloric acid. What is the pH of the resulting solution? Homework Equations Moles of solute = molarity of solvent * volume of solvent The Attempt at a Solution...

Homework Statement 8.9985 g of Na2HPO4 and 4.0211 g of NaH2PO4 * 7 H2O are added to 1 L of 0.20 M KCl in water. KCl does not participate in any way but to maintain ionic strength, at 0.20 M. H3PO4 (aq) + H2O → H2PO4- (aq) + H3O+, Ka1 = 7.11 x 10-3 Ka2 = 6.32 x 10-8 Ka3 = 7.1 x 10-13 (a)...

Homework Statement 2.75 g of mgo(s) is added to 70.0 ml of 2.4 mol/l hno3(Aq) is the concentration that results from the solution acidic or basic? What is the concentration of the ion that is responsible for the character of the solution. What is the pH ? Homework Equations...

Hey! I've been working on this problem - I think it would be easy for a chemist to answer. If anyone can help me out, I'd appreciate it! Suppose I want to create a pH gradient from 3 to 9, in increments of 0.5: pH = (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9) Each pH is in a different...