Among the following elements, which one has the lowest melting point: zinc, titanium, sulphur, or fluorine?

Introduction / Context:
Melting points depend on the type of bonding and the strength of forces holding particles together in the solid state. Metals, molecular solids, and diatomic gases all show different melting point patterns. This question compares zinc, titanium, sulphur, and fluorine in terms of melting point and asks which has the lowest value. Understanding the answer reinforces the idea that small, light diatomic molecules with weak intermolecular forces melt at very low temperatures compared to metals and larger molecular solids.

Given Data / Assumptions:

• Zinc and titanium are metals with metallic bonding.
• Sulphur is a nonmetal that forms S8 molecules in the solid state.
• Fluorine is a halogen that exists as F2 molecules and is gaseous at room temperature.
• We compare their melting points under standard pressure.

Concept / Approach:
Metallic bonding in zinc and titanium is strong, especially in transition metals like titanium, so their melting points are relatively high. Sulphur, as S8 rings, forms a molecular solid with stronger dispersion forces than simple diatomic gases, giving a moderate melting point above room temperature. Fluorine consists of small F2 molecules with very weak London dispersion forces. It is a gas at room temperature and condenses to a liquid or solid only at very low temperatures, indicating a very low melting point. Hence, fluorine has the lowest melting point among the given elements.

Step-by-Step Solution:
Step 1: Classify zinc and titanium as metals, sulphur as a molecular nonmetal solid, and fluorine as a diatomic gas. Step 2: Recall that metals usually have higher melting points due to strong metallic bonds. Step 3: Note that sulphur is a solid at room temperature, so its melting point must be above room temperature. Step 4: Recognise that fluorine is gaseous at room temperature and only forms a solid at very low temperatures, so its melting point is well below zero degrees Celsius. Step 5: Conclude that fluorine has the lowest melting point of the four elements.

Verification / Alternative check:
Approximate data show that titanium melts above 1600 degrees Celsius, zinc melts around 420 degrees Celsius, sulphur melts near 115 degrees Celsius, while fluorine melts around minus 220 degrees Celsius. These values clearly place fluorine at the lowest melting point. The order matches what would be expected from the relative strengths of metallic bonding, molecular forces in S8, and molecular forces in F2.

Why Other Options Are Wrong:
Zinc and titanium are metals with much higher melting points than molecular solids or diatomic gases. Sulphur, though nonmetallic, is still a solid at room temperature and melts only when heated above 100 degrees Celsius, so it cannot have the lowest melting point. The suggestion that all four elements have nearly the same melting point is inconsistent with the fact that some are metals, one is a solid nonmetal, and one is a gas at room temperature. Thus, none of these alternatives match the observed trend.

Common Pitfalls:
Students sometimes rely only on atomic or molecular mass and assume heavier elements always have higher or lower melting points without considering bonding. Another mistake is to ignore the physical state at room temperature, which gives important clues. To avoid these errors, always think about how particles are held together in the solid: metallic bonds, ionic bonds, covalent networks, or weak van der Waals forces in molecular or noble gas solids, and link this to melting behaviour.

Final Answer:
Among zinc, titanium, sulphur, and fluorine, the lowest melting point is shown by fluorine.