Estimation of Amino Acids with Sorenson's Formal Titration
10 Questions
6 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the purpose of using excess formaldehyde in the estimation of glycine purity?

  • To prevent the formation of zwitterions
  • To block the amino group by forming methylene glycine (correct)
  • To enhance the reaction with NaOH
  • To neutralize the glycine solution
  • Why is it important for the formaldehyde solution and glycine solutes to be brought to the same pH before mixing?

  • To maintain stability of the cation formed
  • To prevent zwitterion formation
  • To avoid interference with formic acid
  • To ensure optimal reaction conditions (correct)
  • Why can't amino acids like glycine be estimated by direct titration with standard alkali solution?

  • Neutralization of amino acids by alkali solution
  • Formation of unstable compounds with alkali solution
  • Inability of amino acids to react with alkali solution
  • Amino group interference at the end point (correct)
  • What is the role of NaOH in the estimation process of glycine purity?

    <p>To convert glycine into a form that can react with formaldehyde (D)</p> Signup and view all the answers

    What is the state of glycine in aqueous solution before reacting with formaldehyde and NaOH?

    <p>&quot;Zwitterion&quot; (B)</p> Signup and view all the answers

    What is the purpose of using excess formaldehyde in the estimation of glycine purity?

    <p>To block the amino group by forming methylene glycine (B)</p> Signup and view all the answers

    What is the role of NaOH in the estimation process of glycine purity?

    <p>To convert glycine into a stable cation (C)</p> Signup and view all the answers

    Why can't amino acids like glycine be estimated by direct titration with standard alkali solution?

    <p>Amino group interference at the end point (A)</p> Signup and view all the answers

    What is the state of glycine in aqueous solution before reacting with formaldehyde and NaOH?

    <p>&quot;Zwitterion&quot; incapable of reacting with formaldehyde (C)</p> Signup and view all the answers

    Why is it important for the formaldehyde solution and glycine solutes to be brought to the same pH before mixing?

    <p>To prevent undesirable side reactions during titration (B)</p> Signup and view all the answers

    Flashcards

    Formaldehyde's role in glycine purity

    Blocks the amino group, forming methylene glycine, enabling accurate estimation.

    Equal pH for formaldehyde and glycine

    Ensures optimal reaction conditions, preventing unwanted reactions during titration.

    Direct titration of amino acids

    Not possible due to interference of the amino group at the endpoint of the reaction.

    NaOH's role in glycine estimation

    Converts glycine to a reactive form, enabling its reaction with formaldehyde.

    Signup and view all the flashcards

    Glycine's aqueous state (before reaction)

    Glycine exists as a 'zwitterion' in an aqueous solution before reaction.

    Signup and view all the flashcards

    Glycine's role in zwitterion form

    A zwitterion form of glycine is unable to react with formaldehyde until it is converted.

    Signup and view all the flashcards

    Formaldehyde excess purpose

    Blocks the amino group in glycine, leading to a better determination of the amount of glycine.

    Signup and view all the flashcards

    NaOH's effect on glycine

    Converts glycine into a stable cation form for better reaction with formaldehyde.

    Signup and view all the flashcards

    Amino group interference

    The amino group from glycine causes inaccuracy in titration results.

    Signup and view all the flashcards

    Zwitterion and reaction

    Glycine, in its zwitterion form, is unable to react until it is modified.

    Signup and view all the flashcards

    Study Notes

    Estimation of Glycine Purity

    • Excess formaldehyde is used to ensure complete reaction with glycine, allowing for accurate estimation of glycine purity.
    • The formaldehyde solution and glycine solutes must be brought to the same pH before mixing to prevent uneven reaction rates and ensure accurate results.

    Titration of Amino Acids

    • Amino acids like glycine cannot be estimated by direct titration with standard alkali solution because they do not react with alkali in a straightforward manner.

    Role of NaOH

    • NaOH is used to convert glycine into its anionic form, allowing it to react with formaldehyde and facilitating the estimation process.

    State of Glycine in Aqueous Solution

    • In aqueous solution, glycine exists in its zwitterionic form, which must be converted to its anionic form by NaOH before reacting with formaldehyde.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Learn about the estimation of amino acids, such as glycine, using Sorenson's Formal titration method. This quiz covers the identification of percentage purity of a glycine sample and the determination of the amount of amino acid present in a given solution.

    More Like This

    Chemistry Titration Experiment
    12 questions

    Chemistry Titration Experiment

    VividSydneyOperaHouse avatar
    VividSydneyOperaHouse
    Amino Acids pH Titration
    24 questions

    Amino Acids pH Titration

    CelebratedDubnium avatar
    CelebratedDubnium
    Chemistry: Buffer Solutions and Titration Curves
    21 questions
    Use Quizgecko on...
    Browser
    Browser