Level 1: Core Concepts Check (Aiming for a Pass - 'S')

1. Define: What is an ionic bond?

2. Define: What is a covalent bond?

3. Identify: What type of bonding occurs between a metal and a non-metal?

4. Identify: What type of bonding occurs between two non-metal atoms?

5. Recall: Why do atoms form chemical bonds?

6. Define: What is a cation?

7. Define: What is an anion?

8. List: Give one property of a typical ionic compound.

9. List: Give one property of a typical covalent compound.

Level 2: Connecting the Dots (Aiming for a Credit - 'C')

1. Explain: Describe how a sodium atom (Na) and a chlorine atom (Cl) form an ionic bond in NaCl, mentioning the transfer of electrons and the formation of ions.

2. Draw: Draw a dot-and-cross diagram to show the sharing of electrons in a molecule of hydrogen chloride (HCl). (Atomic numbers: H=1, Cl=17).

3. Explain: Why do ionic substances like salt only conduct electricity when they are molten or dissolved, but not when they are solid?

4. Compare: Explain why a covalent substance like methane (CH₄) has a much lower melting point than an ionic substance like sodium chloride (NaCl).

5. Discuss: What are intermolecular forces, and how do they explain why water is a liquid at room temperature?

Level 3: Exam Challenge (Aiming for a Distinction - 'A'/'B')

1. Analysis: You are given two unknown white crystalline solids, Substance X and Substance Y. You conduct two tests:
   Melting Point: Substance X melts at 801°C. Substance Y melts at 115°C.
   Conductivity: A solution of Substance X in water conducts electricity. A solution of Substance Y in water does not. (a) Based on the evidence, what type of bonding is present in Substance X? (b) What type of bonding is present in Substance Y? (c) Explain in detail how the bonding in Substance X accounts for BOTH its high melting point and its electrical conductivity in solution.