Ph Definition and 512 Threads

Homework Statement A solution is to be buffer at pH = 3:35 with formic acid and formate. (a) How many moles of formic acid and sodium formate are needed if the solution is to change pH by < 0:02 for the addition of 0.02 moles of strong acid? i need help how to set up a problem like...

Homework Statement Im having issues with two parts of this problem, not sure what I'm doing wrong... A lake with a surface area of 12.2 acres (1 acre = 4.840 103 yd2) receives 1.67 in. of rain of pH 4.82. (Assume that the acidity of the rain is due to a strong, monoprotic acid.) How many...

Hi guys, I've got to do a project for school on the investigation of the effect of pH on the enzyme amylase. I am abit lost right now only just started A levels. Can someone suggest how i would carry out this investigation? Equipment and method would be much appreciated! And the results need to...

Hi guys, i have been set some coursework by school on the investigation of the effect of pH on the enzyme amylase. I am abit lost right now only just started A levels. Can someone suggest how i would carry out this investigation? Equipment and method would be much appreciated! And the results...

I understand the henderson-hasselbalch equation, and how the pH of a solution depends on the ratio of acid to its conjugate base. However, I don't understand how this concept can be related to solutions that are extremely diluted. For example, let's say you have 0.00001M acid+c.base...

I had this lab done where we took beets and tested the effects of pH on membrane permeability. We used different concentrations of HCl and NaOH. Why did I get such a strong colour intensity with a test tube that had 0.001 M NaOH? And how do I know this experiment affected the protein...

Homework Statement Select any molecule [from the assigned chapter] that has more than 2 ionizable groups. Write its structures, showing every atom, at pH levels 1 and 7. Homework Equations See below. The Attempt at a Solution http://en.wikipedia.org/wiki/Geranyl_pyrophosphate...

Titrant [HNO2]= 0.10 mol/dm3 v= 25ml = 0.025 dm3 + Analyte [NaOH]= 0.125 mol/dm3 v= 20ml = 0.02 dm3 Question is: What is the ph after adding a volume 10ml of titrant? I know the answer is ph= 4,3 I'm not allowed to use Henderson Hasselbach equation. This is the...

I am having difficulties as to what equation to use to calculate the volume. Can someone please kindly give me some help? Homework Statement What is the volume of 6M HCl required to acidify the mixture of 1g benzaldehyde and 2mL 10M KOH to a pH ~2? Homework Equations MW of...

An increase in the OH- in a solution would result in an increase in alkalinity (baseness). an increase in acidity. a pH of 7. a decrease in pH. i think it would be - an increase in alkalinity, but I am not sure help!

The Ph of 0.3mol/l of a weak base is 10.66, calculate kb. I was thinking of using ph and calculate the concentration of H ions and then calculate poh and OH, but don't know what to do next. Any ideas?

Homework Statement A solution was prepared by dissolving 0.02 moles of acetic acid (HOAc; pKa = 4.8) in water to give 1 liter of solution. a) What is the pH? b) 0.008 moles of concentrated sodium hydroxide (NaOH) was then added to this solution. What is the new pH? (In this problem, you may...

HELP! I just need the steps to figured out these 3 problem. I have the answes but I can't seem to figure out how to do it and my notes aren't helping. thanks! Determine the pH of a solution obtained by titrating 25.00 mL of a 0.107 M solution of a weak base using 75.25 mL of 0.100 M HCl(...

Question A buffer solution is prepared by mixing 600.0 ml of 0.600 M HClO and 400.0 ml of 1.00 M NaClO. Calculate the pH of the solution after 40.0 ml of 3.00 M HCl is added to the buffer. For HClO, Ka = 3.0 X 10^-8. Work so Far A buffer solution os prepared by mixing 600.0 ml of 0.600 M...

Question A buffer solution is prepared by mixing 380.0 ml of 0.250 M propionic acid, C2H5COOH, and 120.0 ml of 0.350 M sodium propionate, C2H5COONa. Calculate the pH of the prepared buffer solution. For propionic acid, Ka = 1.34 X 10^-5. Work thus far We have this C2H5COOH <-->...

Homework Statement What is the pH of the resulting solution when 100.0 mL of 0.10 M H3PO4 is mixed with 200.0 mL of 0.15 M NaOH? Homework Equations Henderson-Hasselbalch, equilibrium constant expressions The Attempt at a Solution I've thought about this question for over an...

Hello, i would really appreciate it if someone could help me with this problem. I would like to know the pH of citric acid at various concentrations. 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 20%. From what i have read it has something to do with its pKa value which for citric acid is...

I'm trying to do this homework problem, and I really am confused about how to do it. I'm familiar with dissociation of weak acids/bases, but I'm pretty confused with this problem(with a strong base and strong acid). The problem is: "40.0ml of 0.20M HCl is mixed with 40.5ml of 0.20M NaOH. a)...

Homework Statement This question refers to a previous question in my book: Calculate the pH of .1 M NaC3H5O2. The question I'm stuck with now: Calculate the pH after .02 mol NaOH is added to 1 L of the *previous* solution. Homework Equations The Henderson-Hasselbalch equation or the simple...

Homework Statement A buffer solution was formed by mixing 30ml of 0.1M sodium acetate and 15ml of 0.1M HCl a) Calculate the pH of this buffer solution. b) Calculate the pH of this buffer solution after the addition of 15ml of 0.1M HCl. Homework Equations [SIZE="4"]pH = pKa +...

Question: TRIS is a weak base. Compute pH of a solution containing .050 moles of TRIS and .020 moles of HCl in a total volume of 2L. pKb for TRIS is 5.92. Use RNH2 to represent TRIS. Equation: pH = pKa+ log ([conjugate base]/[acid]) Work: change equation for pOH: pH = 14-pOH pOH =...

Homework Statement Calculate the final pH of the following solutions: a) 65.0 ml of 0.105 M HCl and 100 ml of 0.118 M sodium acetate solutions are mixed. b) 100 ml of a 0.109 M acetic acid and 100 ml of a 0.123 ml NaOH solution are mixed. Homework Equations pH = pKa = log...

Homework Statement Calculate the pH of the solution a) 23.0 ml of 6.29 M HCl is added to 160.0 ml of distilled water Homework Equations pH = -log [H] [SIZE="4"]Kw= [H][OH] [SIZE="4"]Kw = 1 x 10^-14 The Attempt at a Solution [SIZE="4"]For part a) I found the no.of moles...

im meant to design an experiment (at AS level) and perform it to see how the pH can affect beetroot cell membrane permeability. i don't know where to start. anyone have any experiments?? thanks :biggrin:

In the textbook it stated "In aqeous solutions, the concentration of hydronium ions is always related to the concentration of hyroxide ions. Therefore we can still measure or calculate the pH of solutions of bases like NaOH, even though they are not acidic." The book also stated that pH is a...

Homework Statement What is the final pH of a solution obtained by mixing 200 ml of 0.400 M NH3 with 300 ml of 0.100 M HCl? (Kb = 1.8 x 10^-5) Homework Equations The Attempt at a Solution I used an ICE table and came up with 9.68. Is that correct? Should I have used two ICE tables instead...

Homework Statement find the pH of: 100mL x .20M HOAc + 100mL x.10M Ba(OH)2 The Attempt at a Solution 100x.2 = 20mmol HOAc 100x.1 = 10mmol Ba(OH)2 20-10=10 10/200=.05M pOH = -log(.05) = 1.3 pH=14-1.3=12.7 Is this correct?

Homework Statement Predict whether an aqueous solution of KBr will be acidic, basic, or neutral. Homework Equations KBr(s) → K+(aq) + Br-(aq) Br-(aq) + H2O(l) ← HBr(aq) + H3O+(aq) The Attempt at a Solution The solution will be neutral. I know that this is the correct answer. I just...

what will be the new pH of a 100 lt solution if 1 lt buffer solution of 5 pH is added to it

Homework Statement What is the [H3O+] of acid rain with a pH of 4.23? Homework Equations pH = -log[H30+] pOH = -log[OH-] pH + pOH = 14 The Attempt at a Solution the four possible choices are a. 1.7 x 10^-10 b. 5.8 x 10^-5 c. 2.3 x 10^-4 d. 1.7 x 10^5

How is soil pH affected by soil texture? any sites would be helpful alot.

I know what the formal definition of ph is, and I am comfortable with logarithms, anti-logs, and the laws of exponents. Still, I get confused doing actual calculations and would greatly appreciate your input on the following: Suppose something has a ph of 3.5-How do you calculate the hydrogen...

could the equation - pH=pKa+log([A]/[HA]) - be applied for the case of strong acid? Although the percentage of dissociation of strong acid/base is very high, there still exists a equilibrium, right? secondly, if i tried to explain the resistance in pH of buffer *in terms of* the above...

Hi my question is How does the pH relate to the concentration of Hydrogen ions? what I think is The relationship between the pH and the concentration of Hydrogen ions is that the -log of the hydrogen ion concentration is equal to the pH, but this doesn't seem right at all. can someone...

This is not a homework question, so I cannot give exact values or anything, sorry. If we have to make a buffer solution, and we know the pH and the pKa of the acid we are going to use, would it be true to say that if the pH < pKa, we will need more of the weak acid than salt? If pH > pKa, we...

We have 45.0g of Na3PO4 per liter. We know it is very basic but need the pH. I don't have the answers to all exercises, so if you could check my work, that'd be great. So, we have g, but moles would be more useful. So 45g x (1 mol/163.937) = 2.7 x 10^-1 mol. We know that strong bases...

How do you calculate the pH of 0.001 M NaCl? I was thinking of doing NaCl + H2O ---> HCl + NaOH but I don't know where to go from there if that's even the right step.

I want to ask that there is any situation that the solution of Hydroclauric acid and water can make the pH of this solution gretater than 7.

Hi, I need some help with a few problems. Thanks! (1) You have a pH Electrode that reports a voltage in mV, which is proportional to the hydrogen ion concentration in solution. You also have pH buffers at known pH of say 4, 7 and 10. What do you do to translate the mV reading into pH...

Hello friends! I have a query for which i have been trying to find an answer for a long time but in vain! Can anybody tell me how do we find the effect of pH on amphoteric compounds?I am currently working on Amphotericin B which happens to have both the acidic and the amino groups. I need...

An Introduction to pH and Buffer Solutions Calculations [work in progress] This is a work in progress 1. pH and Strong Acids pH is defined as the negative logarithm of the hydrogen ion concentration in a solution; pH = - log10[H+(aq)]. (From this point forward 'log' will represent log to the...

Hey I have been having a lot of trouble in solving these problems and I have exams soon and I really don't know where to start, I know u aint meant to give the answers so instead would someone please go through all of the steps to finish this! I really need some kinda help, This question was in...

Question is: An unknown solution is 40 times more alkaline than neutral water which has a PH of 7. Determine the PH of the unknown solution. Here is what I have: 40 = (log base 10 x)/(log base 10 7) 40 = 10^(x-7) 10^1.4 = 10^(x-7) 1.4 = x - 7 x = 8.4 The answer is supposed to be...

I have to place two acids and two bases from a previous assignment on a pH scale using the information I acquired during that particular experiment. The problem is, I couldn't get all the materials I needed so I didn't get to do the assignment. I've been able to figure out what vinegar's pH is...

What is the pH of a solution 0.1 M in ammonia and 0.141 M in ammonium chloride? (Kb for ammonia is 1.8e-5) i would really appreciate if someone can pt me in the right direction on how to solve this qn

This problem is driving me nuts. :-p The polyprotic acid, H[SIZE="1"]2SO[SIZE="1"]4 has a complete disassociation at the first step and its pKa for the second step is 1.9. When CaSO[SIZE="1"]4 dissolves ina strong acidic solution of HCl, the final concentration of Ca2+ is 0.03 M and...

I have a question here and i don't really know how to do it. I need to know : What is the pH of a mixture of 30ml 0.1M acetic acid and 30ml of 0.1M NaOH? \[HC_2 H_3 O_3 = 1.8*10^{ - 5} \] I'm not even sure what the equilibrium equation would be! Any help would be appreciated.

i know if you have an acid, say .0001 M HCl, to get the pH you simply take the -log of the acid concentration (which is the same as [H+]), but what if you have a diprotic (H2SO4) or triprotic (H3PO4) acid...do you need to multiply the acid contentration by 2 or 3 to get the new H+ concentration...

K(a) for HX is 7.5 x 10^-12. What is the pH of a 0.15-M aqueous solution of NaX? a. 7.87 b. 1.85 c. 5.97 d. 8.03 e. 12.15 HX --> H+ + X- I found H+ concentration, which is 1.06 X 10-6, then found pH of this, and it is 5.97. I wasn't sure where to go from here so I guessed...

Which one of the following salts, when dissolved in water, produces the solution with the lowest pH? a.NaCl b.NH4Cl c.MgCl2 d.AlCl3 Ammonium chloride My answer lies with b or d since they are both acidic salts, but I think is it d since the K_a is greater...