Powder Flowability and Angle of Repose Quiz
13 Questions
2 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 significance of the angle of repose in powder flowability?

  • A higher angle of repose indicates improved powder flowability.
  • The angle of repose is not directly related to powder flowability.
  • The angle of repose only affects powder flowability if the powder is very fine.
  • A lower angle of repose indicates improved powder flowability. (correct)

    • What is the effect of increasing the concentration of lubricant on the angle of repose?

  • Increasing lubricant concentration only affects the angle of repose in very fine powders.
  • Increasing lubricant concentration increases the angle of repose. (correct)
  • Increasing lubricant concentration decreases the angle of repose.
  • Increasing lubricant concentration has no effect on the angle of repose.

    • What is the relationship between particle size and the angle of repose?

  • The relationship between particle size and angle of repose is complex and depends on other factors.
  • Larger particle size results in a larger angle of repose. (correct)
  • Larger particle size results in a smaller angle of repose.
  • Particle size has no effect on the angle of repose.

    • Which factor is NOT mentioned as influencing the angle of repose?

    <p>Temperature (C)</p> Signup and view all the answers

    The formula Tan θ = h/r is used to calculate what?

    <p>The angle of repose (B)</p> Signup and view all the answers

    What is the primary reason why good powder flowability is essential in pharmaceutical tablet manufacturing?

    <p>Preventing air entrapment in the powder, which can lead to tablet defects. (B), Ensuring uniform weight distribution in each tablet. (C)</p> Signup and view all the answers

    Which of the following factors significantly contribute to powder flowability?

    <p>All of the above. (D)</p> Signup and view all the answers

    How does particle size affect powder flowability?

    <p>Larger particles exhibit better flowability due to reduced cohesion and adhesion. (D)</p> Signup and view all the answers

    What is the main mechanism by which glidents enhance powder flowability?

    <p>Decreasing cohesion between particles by reducing surface friction. (C)</p> Signup and view all the answers

    What is the role of lubricants in powder flowability?

    <p>Reducing adhesion between particles and the tooling surfaces during tablet formation. (C)</p> Signup and view all the answers

    What is the recommended maximum concentration of magnesium stearate as a lubricant in powder formulations?

    <p>1% (A)</p> Signup and view all the answers

    Which of the following methods is a common approach to improve powder flowability when adding excipients fails to achieve the desired outcome?

    <p>Granulation, a process that creates larger aggregates. (B)</p> Signup and view all the answers

    Which of these factors is LEAST likely to directly influence powder flowability?

    <p>Drug solubility in a solvent. (D)</p> Signup and view all the answers

    Flashcards

    Flowability

    The ease with which a powder mass flows, crucial for dosage uniformity.

    Factors Affecting Flowability

    Factors like particle shape, size, roughness, and packing influence powder flow.

    Cohesion

    The attraction between particles that affects their ability to flow together.

    Adhesion

    The attraction between powder particles and container surfaces that can impede flow.

    Signup and view all the flashcards

    Van der Waals Forces

    Weak attractions between particles that influence their flow characteristics.

    Signup and view all the flashcards

    Improving Poor Flow

    Enhancing powder flow by using glidents or lubricants during formulation.

    Signup and view all the flashcards

    Glidents

    Substances like aerosols that reduce cohesion between powder particles.

    Signup and view all the flashcards

    Lubricants

    Substances like magnesium stearate that prevent adhesion during processing.

    Signup and view all the flashcards

    Granulation

    A process of size enlargement where particles form larger aggregates of size 0.1 to 2.0 mm.

    Signup and view all the flashcards

    Angle of Repose

    The maximum angle between the sides of a heap of powder and the horizontal surface.

    Signup and view all the flashcards

    Factors affecting Angle of Repose

    Characteristics like particle size and uniformity that influence the angle of repose.

    Signup and view all the flashcards

    Calculating Angle of Repose

    Using the formula: Tan θ = h/r, where h is height and r is radius of the heap.

    Signup and view all the flashcards

    Role of Lubricants

    Lubricants can lower the angle of repose at low concentrations, aiding powder flowability.

    Signup and view all the flashcards

    Study Notes

    Powder Flowability

    • Flowability is the ease of flow of a powder mass.
    • It's critical for uniform feeding and preventing issues like capping or lamination in pharmaceutical manufacturing.
    • Flowability depends on various factors including particle shape, size, size distribution, surface roughness, packing properties, etc.
    • Powder flowability is its ability to flow in a desired manner in equipment.

    Interaction Between Particles

    • Cohesion (interaction between particles) and adhesion (interaction between particles and container) affect flow.
    • Electrical surface charges, induced by friction, influence flow.
    • Van der Waals forces and surface tension, particularly influenced by moisture, are mechanisms by which particles adhere to each other or to the container.
    • These effects depend on the powder's chemical and physical form. Cohesion and adhesion increase as particle size decreases.

    Improving Poor Flow

    • Adding specific excipients (like glidents and lubricants) can improve flowability.
    • Magnesium stearate is a common lubricant, but its concentration can't exceed a certain amount or it will hurt flow.
    • Granulation involves agglomerating small particles into larger ones. This process increases the particle size and can improve flowability.

    Angle of Repose

    • Angle of repose is the maximum angle formed between the slope of a powder heap and the horizontal plane.
    • Factors affecting the angle of repose include the particle's surface unevenness and non-uniformity, and particle size.
    • Smaller particle sizes lead to higher angles of repose.
    • Lubricants can decrease the angle of repose.
    • Fines (small particles) increase the angle of repose.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Powder Flowability PDF

    Description

    Test your knowledge on the significance of the angle of repose in powder flowability. This quiz covers factors affecting the angle of repose, such as lubricant concentration and particle size. Challenge yourself to identify the relationships and calculations involved in this important concept in material science.

    More Like This

    Friction
    30 questions

    Friction

    NourishingRoseQuartz avatar
    NourishingRoseQuartz
    Angle's Classification Method Quiz
    6 questions

    Angle's Classification Method Quiz

    MatchlessAltoSaxophone avatar
    MatchlessAltoSaxophone
    Angle's Classification of Malocclusion Flashcards
    18 questions

    Angle's Classification of Malocclusion Flashcards

    UnparalleledEcoArt avatar
    UnparalleledEcoArt
    Pharmaceutical Manufacturing Powder Flow Quiz
    10 questions

    Pharmaceutical Manufacturing Powder Flow Quiz

    IncredibleChrysoprase9338 avatar
    IncredibleChrysoprase9338
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser