Summary

• Description:

  The MS Word document contains the Form 4 Chemistry Mid Term 2 Exam 2025 with Marking Scheme. A PDF version is also available upon request.

  Please note: The marking scheme is provided in a separate document.

  The exam paper, titled “CHEMISTRY FORM 4 MID TERM 2 2025 EXAMINATION,” consists of 10 questions and is marked out of 50 marks.

  Topics Covered in the Exam:

  1. Chemical Equilibrium

  • Definition of dynamic equilibrium

  • Stating Le Chatelier’s Principle

  • Explaining the effect of increased temperature on the yield of nitrogen(II) oxide in the reaction:
    N₂(g) + O₂(g) ⇌ 2NO(g) + heat

  • Calculating the volume of nitrogen(II) oxide produced from a given volume of nitrogen

  • Predicting the position of equilibrium when pressure is reduced

  2. Gases

  • Stating Graham’s Law of Diffusion

  • Calculating the time required for a gas (Y) to diffuse, given the diffusion time and relative molecular mass (RMM) of another gas (X) under the same conditions

  3. Chemical Energetics (Thermochemistry)

  • Definition of bond energies

  • Calculating the enthalpy change for the reaction:
    C₂H₄(g) + Br₂(g) → C₂H₄Br₂(g) using provided bond energies and identifying the type of reaction

  • Definition of molar heat of solution

  • Writing a thermochemical equation for the dissolution of sulphuric(VI) acid (H₂SO₄)

  • Calculating the temperature rise (ΔT) when a given mass of H₂SO₄ is dissolved in water, using the provided density and specific heat capacity

  4. Water

  • Definition of hard water

  • Stating two methods for removing permanent hardness in water

  5. The Mole Concept and Stoichiometry

  • Writing the balanced equation for the reaction between hydrochloric acid and calcium hydrogen carbonate

  • Calculating the moles of HCl used and the corresponding moles of calcium hydrogen carbonate

  6. Atomic Structure and the Periodic Table

  • Determining the number of neutrons in an element (Y) based on its atomic and mass numbers

  • Drawing the ionic structure of element Y

  • Analyzing a periodic table grid:

    • Identifying the position of an element (M) with atomic number 1 and discussing possible placements

    • Naming the family groups for specific elements (e.g., G and T; K and H)

    • Selecting the lightest noble gas from given options

    • Comparing the reactivity of elements H and K, with justification

    • Comparing the atomic radii of elements G and X, with explanation

    • Writing the formula of a compound formed between element Q (same group as P) and oxygen

  7. Metals

  • Stating two methods to prevent rusting of a metallic spatula

  8. Non-Metals (Oxygen)

  • Writing the formula of the chemical used in the laboratory preparation of oxygen gas

  • Stating two commercial uses of oxygen

• File Size:

  32.21 KB
• Length:

  5 pages
• Category:

  Exams
• Level:

  Form 4
• Subject:

  CHEMISTRY
• Posted By:

  Caleb_Peter

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