Ph Definition and 512 Threads

Hello there, I've got a question here which asks me to calculate how much (in mol/L) of buffer solution to add to 1 litre of solution to resist the change away from a pH of 7.0. a) if there was an increase of 3.99367 x 10-8 of [H+] ions Because the question is talking about pH in a...

Homework Statement 24 ml of 1.5 M solution of unknown acid is titrated with 54 ml 2 M NaOH. The unknown acid is triprotic. If the unknown acid is strong, what is the pH of this acid before titration Homework Equations Mvn= Mvn to find that it was tri-protic. The Attempt at a...

Does the medulla monitor blood pH or is it only the receptors in the heart (aorta / carotid bodies)?

I am working on making Meads (Honey wine) and after speaking to a master Vinter he advised I lower the pH of my starting water & honey mixture to 3.5 for various reasons. I'm interested in experimenting to see if this gives a noticeable taste difference to the mead. I know honey is Basic but...

I have 60,000 LBS of a NaOH solution with a pH of 12.6. I need to be able to calculate the amount of 25% H2SO4 to add to bring the pH down to below 10. Is this possible to calculate?

If given total alkalinity of a solution, and total carbonate concentration, is it possible to find the pH of that solution? Total alkalinity = [OH]- + [HCO3]- + 2 x [CO3]2- - [H]+

Homework Statement If the Tris buffer was exactly pH=9.0, calculate expected pH value after addition of 1 ml of 0.05 HCl. Buffer: 4 ml of 0.01M Tris, pH 9.0 HCl: 1 ml of 0.05M HCl Homework Equations H-H: pH=pKa+log[A-]/[HA] The Attempt at a Solution 9.0=8.21+log[A-]/[HA]...

I've been working on this one for a few days, and I just can't seem to get the right answer. Consider the reaction I2(s) --> I- (aq) + IO3- (aq) Balanced= 3I2 + 6OH- --> 5I- + IO3- + 3H2O deltaG°= -153.8 kJ/mol The question: What pH is required for the reaction to be at equilibrium...

Need urgent help with a manufacturing problem. Our company built a product that is testing in spec for propionic acid and ammonia, but out of spec for pH. Desperate for this answer. The total product build is 24166.246 KG. The amount of propionic acid added is 15949.723 KG, which puts...

1. A buffer system commonly used in the biochemistry lab uses a substance abbreviated TRIS, and it's conjugate acid TRISH+. A Buffer is prepared with [TRIS] = 0.60M and [TRISH+]= 0.30M. What is the pH of this buffered System? The Ka for TRISH+ is 1.20 x 10^-6 [H+]=Ka [HA]/[A-] (Equation...

Hi I have done some research into changing the pH of an acid and I have gotten mixed answers I have Nitric Acid of pH3 and I want to increase it to approximatly pH10. I have deionized water and want to add it to the Nitric Acid until its pH is approximatly 10. I have come across...

I have two questions about pH of buffers. It's a general chemistry class, but the questions aren't similar to anything we've had yet. Homework Statement A buffer is prepared by adding 0.96 L of 0.96 M HCl to 762 mL of 1.4 M NaHCOO. What is the pH of this buffer? [Ka(HCOOH) = 1.7 × 10-4]...

Hi all I have been reading over difference sites when they discuss pH and water and acids. I have under stood most of it. If I change the pH of an acid of say 3, to basic, i add water and this raises the pH of the subatance What I want to know is, does the molarity matter and type of...

Homework Statement A Chemist wishes to prepare 250mL of buffer that has a Ph of 4.50. Starting with 100mL of 0.12 mol L acetic acid and a supply of 0.10 mol L NaOh. 1) explain how this can be done 3) how much 0.20 molL NaOH must e added to this buffer to raise the pH to 5.1? 3) if the...

This should be an easy one for some of you, but it's difficult to me because of my lack of chemistry knowledge. This is not a homework problem, but a calculation I need to do for my research. I need to calculate the pH of a 1 Liter solution containing 0.000077 M HCl and 0.03 M Na-HCO3. (not...

Homework Statement A particular sample of vinegar has a pH of 2.90. If acetic acid is the only acid that vinegar contains (Ka = 1.8 x 10-5), calculate the concentration of acetic acid in the vinegar. Homework Equations Ka = [Products]/[Reactants] pH = -log[H+] The Attempt at a...

Homework Statement You have a 1L of a 2M HCl solution. Assume that the HCl completely ionizes. a) Calculate the pH of the solution right now. b) You now add V litres of water to the solution. Find the pH of the new dilute solution in terms of V. Homework Equations pH = -log[H]...

Homework Statement The assignment is to create a pH buffer in lab. My assignment is pH 0.5. Homework Equations [H+] = (Ka)([HA]/[A-]) log [HA] = pKa - pH + log [A-] The second equation was provided by the instructor, the first is from the textbook. The Attempt at a Solution...

I am a little confused about the meaning of pH, especially when you have a basic solution. I know that pH = -log[H^{+}] , but I don't understand how you can have a pH for a basic solution. Don't basic solutions only produce hydroxide ions? I know that pH + pOH = 14 but why this equation be...

Homework Statement Three milliliters of a 2.0 M solution of HCL are added to 1 liter of buffer solution containing 0.40 moles of the weak acid, propanoic acid (Ka = 1.4 x 10-5) and .50 moles of its conjugate base, sodium propanate. 1) find the ph of the buffer solution 2) find the ph when...

What is the pH of the solution formed when 0.040 mol KOH is added to 2.00 L of 0.020 m HCl? Hello all! I'm really struggling with this. I set up the change table with the reaction of KOH + HCl <> H2O + KCl, and so I end up with Ka = x/(.01-x)(0.2-x). What Ka value would I use? I may be...

Hi there, I was wondering if anyone could help me with 3 questions: 1) Without pH papers, how do you calculate the pH of a 5% H2SO4 (sulfuric acid) solution? I know vinegar is a weak acid, but would a 5% acetic acid have the same pH of a %5 H2So4 solution? 2) If a non-polar solvent...

Hi there, I was wondering if anyone could help me with 3 questions: 1) Without pH papers, how do you calculate the pH of a 5% H2SO4 (sulfuric acid) solution? I know vinegar is a weak acid, but would a 5% acetic acid have the same pH of a %5 H2So4 solution? 2) If a non-polar solvent such...

I'm working on a lab for my chem class and we have to calculate all of the different ion concentrations within some titrations that we did. Here I have to calculate the concentration before anything is added. Na+ + C2H3O2- + H2O → HC2H3O2 + OH- + Na+ the pH is 8.4458 for a 30.0 mL NaC2H3O2...

Hello, I would like to know about, How to change the 3 Phase supply frequency smoothly over a wide range(for example 1Hz - 100Hz)? suggest methods if any exists other than mentioned below : 1)Not using Variable frequency drives 2)Not using MG set Pl note that i want to know, how to...

Homework Statement Calculate pH of the 1,96% solution of H3PO4 (ρ≈1 g/cm^3). Take in account only the first constant of dissociation (7,5 * 10^-3 mol/cubic dm). The reduction of the concentration of H3PO4 because of dissociation can be ignored. % = 1,96% ρ (H3PO4) ≈1 g/cm^3 K = 7,5 *...

hi everyone i am having trouble figuring out how to determine the optimal temperature and optimal PH level of an enzyme? i have a picture of the question uploaded here http://tiny.cc/3kude [can someone explain to me what to do because i don't even know where to start:(

Hello, I have a problem with this task: "Water with pH 5 and reduction potential +0.30 V flows through copper pipe at 25 °C. Calculate how much copper dissolves (in ppm) in water due to corrosion of this pipe. Standard reduction potential of copper Cu0/Cu2+ is 0.34 V." I spent lot of...

Ok so i have this question to figure out. What is the pH of a solution having an H2CO3 concentration of 10-7 mol l-1?Now here is the info I've been given to learn about pH in my lecture notes. That pH is the negative log to base 10 of the concentration of hydrogen ions in a solution. It says...

Homework Statement x mole of a strong monoacidic base is dissolved in one litre of water. The pH of the solution will be (a)-log x (b)14-log x (c)14+log x (d)-log (14-x) Homework Equations The Attempt at a Solution For instance i assumed that the base is NaOH but it does not...

I see a lot of quacky sites about acid/alkaline body chemistry claiming that lemon juice and orange juice make the body alkaline. They both contain citric acid, orange juice also has lots of potassium... I cannot think of any mechanism whereby citric acid would somehow cause a persons body to...

Homework Statement Determine the pH of a salt solution produced from the reaction of NaOH and HCl -no values were given :s Homework Equations I have no clue to do this The Attempt at a Solution Don't even know where to start!

Homework Statement There is 400 mL of 0.2 M histidine buffer- pH 11. Find the moles of HCl that are needed to change the pH to 3.2. Homework Equations pH= pKa+log[b]/[a] The Attempt at a Solution First, this is how you would go from acid to base (acid-->base): 1. There is 400 mL of 0.2 M...

Homework Statement An buffer is made from a 0.1M acid and a 0.25 M salt. According to the equation pH = pKa - log[acid]/[base] the ratio acid:base is 1:2 What volumes are required to make a 1 dm3 solution? Homework Equations The Attempt at a Solution According to the 1:2 ratio we would need...

Homework Statement how would you make a 5pH solution from citric acid(1L) Homework Equations pH= log(H+) The Attempt at a Solution So I will try to work backwards from the [H+] antilog(-5) = 10^-5 M H+ needed this number can be divided by 3, because citric acid is...

Hi to all, I'm in this problem: I've got to prepare a solution of Ca(OH)2 with pH=13.2 . On Perry I read that the solubility value of Ca(OH)2 at T=25°C is 1.65 g/L, so a solution with water and Calcium Hydroxide cannot reach pH=13.2. So I was suggested to prepare the mixture in the following...

This is certainly NOT a homework assignment. I am a medical student and we are learning about oral flora, I read that the safe zone for enamel is a pH of 5.5, and as a diet soda drinker I am curious if this is even possible. I probably should remember how to do something like this. The...

Homework Statement Calculate the pH of a solution of L-glutamic acid in which the ionic species with a net charge of -1 is 5 times greater than that of the isoelectric structure. (Refer to pKa Table at end of problem set). Homework Equations pKa for glutamic acid: -COOH = 2.19...

Homework Statement The problem states: "Draw the chemical structure of ATP at a pH of 7. Homework Equations The Attempt at a Solution The textbook diagrams the phophate groups as unprotonated, but since H3PO4 has a pKa of <7, I was thinking that maybe each phosphate group would have lost one...

How to stabilize pH of the solution that containes silica? Hello, I have a problem with adjusting the pH of my solution to value 7. It contains these chemicals: Na2SiO3, CaCl2, KCl, Na2SO4, NaHCO3 and NaCl. The initial pH (after adding all of these stuff) is around 10. The problem occurs...

Here's a quickie. Since the pH scale is based on powers of 10, would a pH of 12 indicate that a substance is 10^6 times more basic than a substance with a pH of 6?

I need some help calculating basic chemistry. I need to know how much ammonia I need to add to a volume of water to reach the appropriate pH level. I have 50 cubic meters of demin water that I need to raise to a pH of 11. Volume is not flowing. I am using aqueous ammonia of 25%...

What is the mechanism of pH scale?

Is there any relationship between the pH of seawater and any properties of the sand at the beach? If so, what/ why/ how? Context: I am writing a report for my Soil Mechanics course, for which we analysed some sand we collected at the beach, as well as some seawater. One of the key properties...

Homework Statement Shells of mussels are mainly of calcium carbonate. IUsually the shell is stable and its content is in equilibrium with the surrounding. Mussels need to build up or reduce their shell, however, for additional protection or during growth. They achieve this by changing the...

Hey.. so we have this formula pH=pKa+log([A-]/[HA]).. If we add lots of water, the concentration of both A- and HA decrease proportionally so the pH doesn't change.. But this is weird. If the volume increases by large amounts in an acidic solution, shouldn't at least HA decrease in...

My book says that you cannot use the Henderson-Hasselbalch equation to find the pH at the equivalence point when titrating a weak acid with a strong base... I was wondering why not? it says that instead you must use the Kb of the conjugate base and that we find that from the Kw and the Ka...

An buffer solution consists of a mixture of a weak acid and its salt (conjugate base and a cation) or a mixture of a weak base and its salt (conjugate acid and an anion). When you titrate (for example) a weak acid with a strong base, then at the half equivalence point, there are equal...

Homework Statement A current of 10.7 Amps is applied to a 1.30 L solution of 0.550M HBr converting some of the H+ to H2(g), which bubbles out of solution. What is the PH of the solution after 77 minutes. Homework Equations The Attempt at a Solution (10.7 C/s)(1 mol e/96485 C)(2...

I saw this video on a car cleaning product. In it he talks about the improtance of pH balance and how it effects metals. I'm not a chemist, and it's been a long time since I took undergrad chemistry. You can see he does a little lab experiment with the metals in the various pH cleaning solutions...