Question

The compound that has the highest melting point amongst the following is:

• A. Methane
• B. Sodium chloride
• C. Ammonia
• D. Ethanol

Hint:

The melting point of (NaCl) is approximately 801°C, whereas Methane melts at -182°C. That is a massive difference!

Answer 1

The Correct Option is B

To determine which compound has the highest melting point among the given options, let's analyze each compound individually:

1. Methane (CH₄): Methane is a simple hydrocarbon compound with weak van der Waals forces. Its melting point is quite low, around \(-182.5^\circ C\).
2. Ammonia (NH₃): Ammonia is a polar compound with significant hydrogen bonding between molecules. Its melting point is higher than methane but still relatively low, at around \(-78^\circ C\).
3. Ethanol (C₂H₅OH): Ethanol also utilizes hydrogen bonding due to the presence of the hydroxyl (-OH) group. Its melting point is \(-114.1^\circ C\), which is higher than methane but still lower than many other substances.
4. Sodium chloride (NaCl): Sodium chloride is an ionic compound. Ionic compounds are known for their strong electrostatic forces of attraction between oppositely charged ions, which require significant energy to break. Therefore, sodium chloride has a very high melting point of about \(801^\circ C\).

Among the compounds listed, sodium chloride (NaCl) stands out due to its ionic nature, resulting in a much higher melting point compared to the other molecular compounds (methane, ammonia, and ethanol) that rely on weaker intermolecular forces.

Conclusion: The compound with the highest melting point is Sodium chloride.