Lesson Plan: C2.3.03


LESSON PLAN
Teacher Subject Period Date Year Ability LSA/Other Support
Science

Context and
Landmark
Assessment		 C2.3.03
Landmark Assessment: Progress Observation Opportunity
Remember to have high expectations
Lesson Title: Today we are learning about
How can we use paper chromatography to identify an unknown mixture?
Remember to check for PROGRESS
Focus on Knowledge, Skills and Understanding
Success Criteria: You will show your learning by...
  1. Chromatography can be used to separate mixtures and can give information to help identify substances.
  2. Chromatography involves a stationary phase and a mobile phase.
  3. Separation depends on the distribution of substances between the phases
  4. The ratio of the distance moved by a compound (centre of spot from origin) to the distance moved by the solvent can be expressed as its R value
  5. RT = distance moved by substance / distance moved by solvent
  6. Different compounds have different R values in different solvents,
  7. Rf values can be used to help identify the compounds.
  8. The compounds in a mixture may separate into different spots depending on the solvent but a pure compound will produce a single spot in all solvents.
  9. Students should be able to explain how paper chromatography separates mixtures
  10. Students should be able to suggest how chromatographic methods can be used for distinguishing pure substances from impure substances
  11. Students should be able to interpret chromatograms and determine R values from chromatograms
  12. provide answers to an appropriate number of significant figures. (MS)
  13. Elements and compounds can be detected and identified using instrumental methods. Instrumental methods are accurate, sensitive and rapid.
  14. Students should be able to state advantages of instrumental methods compared with the chemical tests in this specification.
Think about how you can match the needs of ALL students
Keywords:
  • Instrumental method: The use of instruments to separate, identify, and quantify matter. (1)
  • Rf Value: In chromatography is the distance travelled by a given component divided by the distance travelled by the solvent front. (1)
  • Stationary phase: The phase of a chromatography system on which the materials to be separated are selectively adsorbed. (1)
  • Mobile phase: flows through the stationary phase and carries the components of the mixture with it. (1)
  • Chromatography: A technique for the separation of a mixture by passing it in solution or suspension through a medium in which the components move at different rates. (1)
Links: Literacy, Numeracy, SMSC, British values
Memory Anchor:

AFL/Key Questions:
  1. What can Chromatography be used to separate?
    Chromatography can be used to separate mixtures such as inks and can give information to help identify the substances from which it is made.
  2. What are the names of the two phases involved in chromatography?
    Stationary phase and mobile phase.
  3. What does seperation depend on?
    Separation depends on the distribution of substances between the phases.
  4. How should the Rf value be expressed?
    The ratio of the distance moved by a compound (centre of spot from origin) to the distance moved by the solvent
  5. How is the Rf value calculated?
    Rf = distance moved by substance / distance moved by solvent
  6. How do the Rf values of compounds change in different solvents?
    Different compounds have different R values in different solvents.
  7. How can compounds be identified?
    Rf values can be used to help identify the compounds.
  8. How many spots are produced by a pure compound compared to a compound in a mixture?
    The compounds in a mixture may separate into different spots depending on the solvent but a pure compound will produce a single spot in all solvents.
  9. How can paper chromatography be used to separate mixtures?
    A spot of each mixture is dropped onto the start line of the paper chromotography. The paper chromatogram is introduced to a solvent and left for seperation to take place.
  10. How can chromatographic methods can be used for distinguishing pure substances from impure substances?
    The compounds in a mixture may separate into multiple spots depending on the solvent, but a pure substance will always produce a single spot in all solvents.
  11. How can chromatograms be used to determine R values?
    The R value can be calculated and compared. RT = distance moved by substance / distance moved by solvent
  12. How can elements and compounds be detected?
    Elements and compounds can be detected and identified using instrumental methods. Instrumental methods are accurate, sensitive and rapid.
  13. What are the advantages of instrumental methods compared with the chemical tests?
Identify questions for high, middle, low and identify questioning techniques- Challenge questions

Learning Phases/Episodes
Think about how you can match the needs of ALL students
Differentiation: AGT, SEND, LLL, Disadvantaged
Remember to check for PROGRESS
Starter Activity Differentiation and Challenge question/task
  • Students to copy and complete the keywords.
  • Teacher reveals missing letters; Students correct mistakes;
  • Discuss the scientific meanings of the words.
  • Students to write down the definitions of the most important / new keywords.
  • Discuss the 'Memory Anchor'.
    • What does it show?
    • How does it relate to the what we are learning about today (title)?
Think about PACE – Develop, consolidate and deepen knowledge, skills and understanding
Teacher or Student lead? Differentiation and Challenge question/task
Progress Check Extension
Remember to give time to apply knowledge, skills and understanding
Teacher or Student lead? Differentiation and Challenge question/task
Progress Check Extension

Teacher or Student lead? Differentiation and Challenge question/task
Progress Check Extension

Teacher or Student lead? Differentiation and Challenge question/task
Progress Check Extension


Plenary Differentiation and Challenge question/task
  • Students to answer the 'Key Questions' with learning partners.
Progress Check
  • Teacher to reveal and discuss the answers to the questions.
 Extension
  • What have learnt about the 'Big Ideas' today?

Homework Differentiation and Challenge question/task