Summary

• Description:

  The MS Word document comprises Form 3 Chemistry Mid Term 2 Exam 2025 with Marking Scheme. The PDF version is also available upon your request.

  The marking scheme is in a different document.

  The exam paper, titled "CHEMISTRY FORM THREE MID TERM 2 2025 EXAMINATION" in the document, contains 12 questions and is marked out of a total of 51 marks. It should be completed by learners within a duration of 1 hour and 20 minutes.

  The topics and skills assessed in the exam include:

  • Gas Laws and Stoichiometry:
    • Stating Gay Lussac's Law.
    • Calculations involving mass and volume of gases at r.t.p (e.g., decomposition of hydrogen peroxide).
    • Calculations using the combined gas law.
    • Determining empirical formula from experimental data.
    • Calculations involving Graham's Law of diffusion.
  • Periodicity and Atomic Structure:
    • Explaining trends in melting points of elements based on their atomic numbers and bonding.
    • Comparing reactivity of elements (e.g., Group 1 metals with chlorine).
    • Writing chemical equations for reactions of elements (e.g., phosphorus with oxygen).
    • Defining ionization energy and explaining trends (e.g., comparing 1st ionization energy of Aluminium and Sodium).
  • Chemical Bonding and Structure:
    • Explaining differences in melting points based on structure and bonding (e.g., phosphorus(III) chloride vs. sodium chloride).
    • Explaining differences in electrical conductivity of molten ionic compounds versus covalent compounds.
    • Explaining properties of allotropes of carbon (diamond and graphite) based on their structure and bonding.
    • Drawing dot and cross diagrams to show bonding (e.g., phosphonium ion, PH₄⁺).
  • Redox Reactions and Reactivity Series:
    • Analyzing reactions in a setup involving the reduction of iron (III) oxide by carbon.
    • Writing equations for reactions occurring.
  • Acids, Bases, Salts, and Separation Techniques:
    • Identifying mistakes in an experimental setup for gas preparation.
    • Describing methods to obtain a pure salt from a mixture.
  • Qualitative Analysis:
    • Describing a chemical test to confirm the presence of water.
  • Industrial Chemistry (Solvay Process):
    • Understanding key terms (e.g., ammoniated brine).
    • Identifying the main source of carbon (IV) oxide.
    • Stating recyclable wastes in the process.
  • Chemistry of Air:
    • Identifying components of air based on their chemical properties/reactions.
  • Laboratory Procedures and Observations:
    • Interpreting experimental setups and observations.
• File Size:

  50.61 KB
• Length:

  5 pages
• Category:

  Exams
• Level:

  Form 3
• Subject:

  CHEMISTRY
• Posted By:

  Caleb_Peter

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