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    Friendly neighborhood students,

    Can any of you explain to me what Titration is and how is it useful?
    I need to write an essay in about weighing and preparing solutions and titration is part of the experiment!

    If you have time can you also explain to me what a buffer and an HPLC analysis are?

    Thank you for your time!
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    Titration is usually seeing how much acid/base it takes to neutralise something(base/acid) but can be other stuff, not sure what others though. When making a solution you usually have to dissolve something, im not an expert on preparing solutions so i'd google or maybe another tsr guy can help you out
    Buffer is a solution which minimizes changes in pH when small amounts of an acid/base are added. Can't remember much about HPLC
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    (Original post by Eloades11)
    Titration is usually seeing how much acid/base it takes to neutralise something(base/acid) but can be other stuff, not sure what others though. When making a solution you usually have to dissolve something, im not an expert on preparing solutions so i'd google or maybe another tsr guy can help you out
    Buffer is a solution which minimizes changes in pH when small amounts of an acid/base are added. Can't remember much about HPLC
    I will wait for other answers but let me +rep you for this very clear and easy definition
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    (Original post by Prospekt117)
    Friendly neighborhood students,

    Can any of you explain to me what Titration is and how is it useful?
    I need to write an essay in about weighing and preparing solutions and titration is part of the experiment!

    If you have time can you also explain to me what a buffer and an HPLC analysis are?

    Thank you for your time!
    I can explain all of these things to you, but it would be a much better use of your time if you went away and researched it yourself; you'll learn better that way If you don't understand things afterwards, then come back and ask specific questions!

    To get you started, try googling the follwing: "chemistry titration", "buffer" "standard solution preparation" "hplc"/"high performance liquid chromatography"
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    (Original post by Revd. Mike)
    I can explain all of these things to you, but it would be a much better use of your time if you went away and researched it yourself; you'll learn better that way If you don't understand things afterwards, then come back and ask specific questions!

    To get you started, try googling the follwing: "chemistry titration", "buffer" "standard solution preparation" "hplc"/"high performance liquid chromatography"
    Ok so first things first: about Titration.

    Titration is part of the process of Volumetric Analysis, which is aimed to finding the concentration of a solution!

    Volumetric Analysis revolves around the concept of Equivalence Point which means what exactly? From what Ive understood in order to calculate the UNKNOWN concentration of a solution, this must react with a solution whom concentration is KNOWN (standard solution), and the equivalence point must be reached! When is it reached exactly?

    Can any of you provide an example of how to reach the equivalence point also showing the calculations? Also is there a standard "standard solution" or it depends on the unknown?

    edit: Titration is basically adding one reactant to the other reagent until the ratio of quantity of the two is exact, balanced! Am I anywhere near?

    Thank you for your help! we will look at the others once this one is very clear! Revvd Mike +repped
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    (Original post by Prospekt117)
    Ok so first things first: about Titration.

    Titration is part of the process of Volumetric Analysis, which is aimed to finding the concentration of a solution!

    Volumetric Analysis revolves around the concept of Equivalence Point which means what exactly? From what Ive understood in order to calculate the UNKNOWN concentration of a solution, this must react with a solution whom concentration is KNOWN (standard solution), and the equivalence point must be reached! When is it reached exactly?
    The equivalence point is when the components as shown in the balanced equation have exactly reacted together with no excess of either.

    (Original post by Prospekt117)
    Can any of you provide an example of how to reach the equivalence point also showing the calculations? Also is there a standard "standard solution" or it depends on the unknown?
    Example would be adding 0.1M HCl dropwise to 25ml unknown NaOH solution using phenolphthalein as an indicator.

    When the solution turns colourless (from red) the equivalence point has been reached and all of the NaOH has been neutralised. This gives you Volume(NaOH)
    needed to reach equivalence.

    Calculation.
    --------------
    Moles(HCl) = Moles(NaOH)

    Therefore:

    Molarity(HCl) x Volume(HCl) = Molarity(NaOH) x Volume(NaOH)

    rearrange to find Molarity(NaOH)

    -------------------------------------------------------------------------------

    The actual reagents and indicator used entirely depend on the unknown solution. Your other reactant obviously must react with it and there must be some indicator to show when the equivalence point is reached.

    (Original post by Prospekt117)


    edit: Titration is basically adding one reactant to the other reagent until the ratio of quantity of the two is exact, balanced! Am I anywhere near?
    That's about the size of it
    (Original post by Prospekt117)

    Thank you for your help! we will look at the others once this one is very clear! Revvd Mike +repped
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    Ok using what I have acquired here this is the first part of my lab report!

    Introduction:
    The Laboratory Session this write-up is aimed to review revolves around the concept of Volumetric Analysis. This is the procedure used in order to find the unknown concentration of a solution by reacting it with a solution of known concentration (standard solution) until the components as shown in the balanced equation have exactly reacted together with no excess of either. This is called Equivalence Point and in order to reach it, Titration is used.
    Titration is the process of adding a certain amount of one reactant to the other reagent until the ratio of quantity between the two is exact. In the Laboratory this is recognizable through the use of chemical indicators, substances that, when a certain ratio between the concentrations of the reactants is reached, will change colour (“endpoint”). For every reaction the appropriate indicator must be chosen so that its endpoint coincides with the equivalence point of the said reaction.
    Tell me if I should change something or if it's good enough in your expert opinion! I wanted to proceed with the "acid-base titration" which seems to be the whole point of the lab session im doing the write up for.

    This is an extract from my lab manual:

    Procedure – Experiment 3 – Titration:
    Titration is a laboratory technique used to determine the concentration of an unknown reagent using a standard concentration of a known reagent. The standard reagent and the unknown reagent react with one another and when the reaction is complete this is referred to as the “endpoint”. The standard solution used in the titration is referred to as the "titrant". In order to visualise the “endpoint” a chemical indicator is added to the reaction mixture. For acid/base titrations this can be in the form of a colour change for example Methyl Red changes from yellow under acidic conditions to red under basic conditions.
    At the “endpoint”:
    HCl + NaOH ? NaCl + H2O
    (H+)(Volume of titrant required to reach end point) = (OH-) (Volume of unknown)

    We can use this equation to calculate the strength of an acid or a basic solution

    Titration
    1. Dispense 10ml of the unknown solution into a 250ml conical flask.
    2. Add 2 drops of the methyl red indicator solution, the solution will turn pink.
    3. Fill the burette with 0.1M NaOH.
    4. Add the 0.1M NaOH to the unknown solution drop wise using the burette.
    5. Swirl the conical flask after each addition.
    6. Record the point at which the solutions turns from pink to yellow in colour.
    7. Record the amount of 0.1M NaOH added from the burette.
    8. Using the above reaction equation, calculate the molarity of the unknown solution.

    Analysis:
    In preparation for the tutorial, please ensure that you can report on the accurate weighing of the powder in the bag and that you have answered all questions asked. Using the information gained in the laboratory session, establish the molarity of the acid in the brown bottle and complete the calculations given below:
    How you would prepare the following solutions?
    Note: All solutions should be prepared in water unless otherwise indicated
    1. 10mg/ml malaic acid potassium salt (C4H3O4K) in a total volume of 50ml.
    2. 5g/L sodium bicarbonate (NaHCO3) in a total volume of 2L.
    3. 0.01M dipotassium hydrogen phosphate (K2HPO4) in a total volume of 250ml.
    4. 2M sodium chloride (NaCl).
    5. 100ppm lead (Pb) in 1000ml.
    6. 0.1M sodium chloride (NaCl) and 0.5M potassium chloride (KCl) in a total volume of 5L.
    7. Mobile phase containing 70% buffer (prepared by you earlier) and 30% methanol. The total volume should be 1000ml.
    8. A 5 millimolar solution of glucose (C6H12O6)
    This was the first thing I did in the Lab, although me and my lab partner didnt do it correctly and had to repeat it, getting some time from the "weighing the powder, making the standard solution" bit which at the end of the lab i didnt have completed....

    Anyway ignore the last calculations, I will work them out this afternoon! I think I should continue my essay by introducing what an acid-base titration is. What do you think?

    edit: an acid-base titration is done by reacting an acid with an alkali until the two are neutralized! The example chargo gave me was an acid-base titration and I think the process given in the lab manual is one too! Am I correct?

    Thank you for all your huuge help and support!
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    Guys I hate to stress it but Im working on a project worth 40% of my module mark!
 
 
 
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