Homework Statement
You are titrating a 75 mL volume of 33 mM lactate buffer (pKa 3.86) with 1.3 M HCl (starting fully deprotonated). What is the pH after you have added 1 mL of the HCl? Give 2 decimal places
Homework Equations
pH = pKa + log[A-/HA]
The Attempt at a Solution
I don't...
Homework Statement
titration method is more accurate than collection of carbon dioxide over water method to solve stoichiometry equation.
Homework Equations
what are the 3 reasons?
The Attempt at a Solution
some carbon dioxide has leak into the air, carbon dioxide is partially...
Neutralization by Acid-Base Titration Problems !HELP!
Hey guys, could you please take a look at my work and let me know if I did it correctly or not? I'm not sure if I did, so if I did anything wrong I'd really appreciate if you could explain! Thanks!
1. A sample of solid potassium...
Homework Statement
I titrated an unknown sample with a Sodium Hydroxide 250cm3 with 0.1M Concentration. I titrate and used up 17 cm3 using a Hydrochloric Acid to neutralise the NaOH. I have to find out the Mole of the unknown substanceHomework Equations
I forgot the equations of titration, all...
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...
Hello, I have to preform a titration on a alkali substance but do not have the neccesary equipment to do so. I was hoping a strip of litmus paper submerged in the solution could be used as an indicator and a small plastic syringe could be used instead of a buret. The exact concentration does not...
Homework Statement
There was this Question in my book:
About 40 mls of 0.1 M solution of a compound sesqui Carbonate (\mathrm{Na}_{2}\mathrm{CO}_3.\mathrm{NaHCO_3}.\mathrm{2H_2O}) are titrated with x mls of .1 M \mathrm{HCl} in the presence of phenolphthalien.And the same compund was...
Homework Statement
For the titration of 50 mL of 0.150 M ethylamine (C2H5NH2), with 0.100 M HCl, find the pH :
a) when 10 mL more of HCl has been added than is required
b) when 75% of the required acid has been added Homework Equations
Maybe Henderson Hasselbalch?: pH = pKa + log (base/acid)...
Hello everyone,
Today I witnessed the titration of a sodium pentobarbital solution with 0.1M HCl. At first, a lot of white precipitate was formed. When more HCl was added the white precipitate disappeared again completely.
Now I am trying to figure out what is going on. As I understand it...
I'm a little boggled by a strangle titration problem that seems to contradict what I know about titration. I hope someone can resolve this seemingly strange phenomenon.
Suppose you have 0.1M of 50mL HCl.
You begin to add 0.1M of NaOH titrant.
Assume that Na and Cl ions do not hydrolyze.
Find...
Homework Statement
You prepare your standardization solution by weighing out 0.0750 grams of standard ascorbic acid (176.12 g/mol) and dissolving it in 50.00 mL of water. You then add ten drops of starch indicator. How many milliliters of 0.015M triiodide solution will you need to reach the...
[Urgent] Titration Problem!
Homework Statement
Titrate 60ml of .15M of HNO3 with .45M NaOH.
A) Give pH of Initial Point.
B) Give pH of Equivalent Point.
C) Give pH of Mid Point.
D) Give pH of End point.
Homework Equations
nacid=nbaseThe Attempt at a Solution
A) I think I did this right...
Hello PF,
I'm doing a Mohr's titration to determine Cl concentration.
The volume I am working with is small, and it is not possible to obtain more. I have 2 uL of analyte to which I add 1 uL of indicator. Then, I add AgNO3 1 uL (0.014M) at a time until the endpoint is reached (color...
I am working on a potentiometric halide titration with Ag+ & don't know where to start with the calculation. I have the raw data but don't know what to do with it. Please help.
Homework Statement
I'm trying to determine the percentage of zinc in an unknown sample. What I did in this lab, was, I titrated the zinc solution (which contained about 4g unknown zinc sample) with Na2EDTA and it took about 20 mL to reach the end point. Before doing this, I standardized the...
Homework Statement
1. Calculate the volume (mL) of 0.100 M H3PO4 required to neutralize 30.0 mL of 0.050 M
2. If 0.2178 g of a diprotic solid acid is neutralized by 44.81 mL of 0.0953 M NaOH, calculate the molar mass of the solid acid.
Homework Equations
Molar Mass = Mass/Moles
Concentration...
Homework Statement
1.The primary standard in thiss experiment is ammonium iron(II) sulphate hexahydrate, (NH4)2Fe(SO4)2*6H2O. Calculate the number of millimoles of ammonium iron(II) sulphate hexahydrate in a 1.0000g sample.
2.Give the balanced equation for oxidation of iron(II) ion by...
In my attempt at standardizing an EDTA solution, the blank solution titration was successful, but the standardization titration failed... here's the procedure of my experiment with some details:
We first prepared a titration blank by using 35mL distilled water, 5mL of pH10 buffer, 5 drops of...
Homework Statement
I am so confused.
I am doing a "Iodometric Titration of Copper in Brass" lab.
We first made a thiosulphate solution by mixing 500 mL water, 12.5 g of Na2S203 * 5H20, and .05 g Na2CO3. This solution is "supposed" to come out to be about 0.1 M. My actual measurements...
Homework Statement
I'm given an unknown amount (around 20mL) of NaH_2PO_4 and I dilute it in distilled water in a 250mL flask. Then I take 25mL of this solution and add 4 drops of thymolphthalein in another flask. Then I titrate it with 0.1M of NaOH until it becoms light blue. I used 22mL of...
Hi, I'm in lab in which we have to titrate 0.09M NaOH into 25mL of 0.1M HCl/HOAc mixture.
Homework Statement
I need help on how to calculate the concentration of HCl and HOAc in the mixture.
0.09M NaOH
1st equivalence point = 14.3mL
2nd equivalence point = 26.9mL
Difference of two...
We used the winkler titration method for our dissolved oxygen experiments.
We added magnesium sulphate and sodium iodine.
For all the methods on the internet it says to use manganese sulphate and potassium iodide.
We have to explain how the method works and the chemistry behind it, so does...
Hi. I'm currently an intern in a biology lab and I have a few questions about titration.
In the lab we are performing an experiment where the goal is to find the concentration of levulinic acid (H8C5O3). To do this, we decided to titrate the acid with NaOH.
Using a KHP standard, we...
They say it's possible to find the growth-rate ie the second derivative of a titration curve on wikipedia. I am interested in finding & deriving such a formula, because I need to know why the growth-rate is so small in the beginning of the titration but it gets so much bigger as you add larger...
Hello,
Can anyone help me with this question or point to where I could obtain an answer...
1. When performing diprotic acid titrations, you may see two clear endpoints or one may be unclear.
a. When do the unclear endpoints occur?
b. In which acids from the list below would you expect...
i have done an isothermal titration calometry with a DNA intercalating drug and a G4 C4DNA sequence. i planned on doing this at different temperatures to obtain a van't hoff enthalpy for the binding reaction. standard papers compare the enthalpy to experimental calorimetric enthalpies to predict...
I posted a picture where I was supposed to label the curve correctly. Can someone let me know if I am correct? I put answers on left side of picture.
Thank you
Homework Statement
6.83 mL of a solution of NaOH is standardized against 3.06 g of potassium hydrogen phthlate
(KHC8O4H4). Calculate the concentration of the base.
Homework Equations
c=n/v
M of KHP = 198.201
The Attempt at a Solution
Here is what I did.
Calculated moles...
Hi guys,
A few days ago we conducted a wine redox back titration in my chemistry class, and my teacher has asked us to calculate to answer all of the questions on a sheet she gave us. Attached is this sheet, outlining the method we followed, the materials used and all the questions she wants...
Homework Statement
In order to achieve a high result in this chemistry assignment, I need to have demonstrated a knowledge of challenging content not discussed in class. Every other part of this assignment I've covered (Intro, method, discussion etc), I am just stuck with the calculations...
Easy Acid-Base titration problem... i think URGENT!
So i just got my final exam for chem 2 back and i missed an A by two question. The thing is these two questions i was for sure i got right but apparently i didnt... here they are:
Use the following information: 50 mL solution of 0.053M HCL...
Hi,
Homework Statement
It is in my chemistry lab course. I had 0.1g of an unknown solid that I diluted in 100ml of distilled water. Then, I took 25ml and titrated it with NaOH (Concentration = 0.0189M). To reach equivalent point (the point where concentration of NaOH is equal to the...
1. This problem has been slowly eating me for the past 2 hours. I've done everything I can but I can't seem to answer it. The pH at the equivalence point in the titration of 100 mL of a 0.1M monoprotic acid solution with a 0.1M strong base solution is 8.12 at 25 degrees C. What is the Ka of the...
Homework Statement
Potassium permanganate (KMnO4) is used to determine the actual concentration of standard solutions containing the nitrite ion. The permanganate ion reacts with nitrous acid according to the following reaction.
2 MnO4- + 5 HNO2 + 5 H+ = 2Mn2+ + 5 NO3- + 3 H2O
Pipet in order...
Homework Statement
The molecular weight of a monoprotic acid HX was to be determined. A sample of 15.126 grams of HX was dissolved in distilled water and the volume were brought to exactly 250mL in a volumetric flask. Several 50mL portions of this solution were titrated against NaOH solution...
Homework Statement
A student wished to determine the percent of acetic acid in commercial vinegar products. Brand X was selected. Three 20.0mL volumes were titrated with a 2.20mol/L sodium hydroxide solution until the indicator phenolphthalein turned pink. The density of acetic acid is...
Homework Statement
Just need someone to confirm whether I am right for this
(The prac is using back titration to find the amount of Nitrogen in Fertiliser)
How would the following affect your experiment:
Burette, pipette and volumetric flask are rinsed with the wrong solution i.e water...
Homework Statement
Assuming stomach acid is 0.1 M HCl(aq), what volume of stomach acid can be neutralized by one antacid tablet?
We have the titration curve we got with .5M HCl titrating a tablet dissolved in 100ml distilled water
Homework Equations
?
The Attempt at a Solution
?
Homework Statement
If .0200L of .100M nitrous acid is titrated using .200M NaOH solution, what will the pH be at equivalence?
Homework Equations
The Attempt at a Solution
I figured out that the volume of NaOH at equivalence is .01L, however I do not know what to do after that...
Hi,
I was wondering why titration is a good method for determining concentrations. For instance to determine the concentraion of a weak acid HAc with a strong base NaOH,
NaOH+HAc --> NaAc+H20
Does this reaction have an equilibrium factor of inifinite or a very big one so that equivalent...
In an experiment titration. The NaOH was added drop wise into HCl in a conical flask.
The number of drops of NaOH was recorded against the varied volume of HCl in the flask.
A graph was to be plotted of number of drops of NaOH on the y-aixs to Volume of HCl on the x-axis.
What would the...
How would adding too much indicator to a base being titrated by an acid affect the result?
Can I list it as a possible error?
If not, can someone please suggest another one? please also say how it would affect the outcome of the experiment and how i would be able to minimise it.
Thanks :)
Homework Statement
OK, so I did this experiment a week ago,
I took 75g of juice and added some 1.5gKI, 7.5cm^3HCl and 5cm^3starch and titrated with Potassium Iodate 0.010M(KIO3). I did this titration again
For the third experiment, I just took 0.1g pure C-vitamin dissolved in some water...
I missed this question on an exam and I was wondering if anyone can explain to me how to do it.Homework Statement
The pKa of acetic acid, HC2H3O2, is 4.76. A buffer solution was made using an unspecified amount of acetic acid and 0.300 moles of NaC2H3O2 in enough water to make 2 Liters of...
In lab I have.
200 mL of a standardised solution of NaOH (of appoximately 0.1 molar concetration)
labeled sample tube containing unknown acid or unknown base.
Indicator: phenolphthalein, Universal, methyl orange.
The aim of this laboratory is to determine the molar mass of an unknown acid...
Homework Statement
This is the lab I did: http://chemistry.depaul.edu/wwolbach/205_207/11.pdf
only steps 1,2, & 3 was performed
Homework Equations
MV1=MV2The Attempt at a Solution
I need help finding the concentration of Ca 2+ and Mg 2+.
I already know the basics of it, but I really don't...
Homework Statement
A sample of powdered milk weighing 1.450 g was mixed with an aqueous buffer of pH 11.5. A few drops of Calagmite indicator were added and the solution required 31.62 mL of 1.539x10^-2 M EDTA to reach the end-point color change.
a. Calculate the concentration of calcium...
Homework Statement
A mixture of phosphoric acid and NaH2PO4 are titrated against 0.151 M NaOH. The first equivalence point is at 0.00345 L and the second equiv point is at 0.01288 M.
The volume of the total mixture was 60 ml.
Calculate the concentration of both the phosphoric acid...
Here's the experiment that I did: http://www.chem.uic.edu/fetzer/chem222/a…
from the first page to half of the second page.
How do I calculate the amount of KCl and KI in the solution?
The graph is suppose to be like a backwards S and it has two endpoints and I don't know how to do the...