Anonymous
Anonymous asked in Science & MathematicsPhysics · 9 years ago

# Why is the melting point of Nacl much higher than that of Alcl3?

Relevance

let us answer from point of chemical properties of ionic and covalent compounds.

we know that ionic compounds have more melting and boiling points than covalent compounds.

compare NaCl , AlCl3 .

NaCl is more ionic than AlCl3 because ionic character depends on size of cations as here anions are same more the size more the ionic character.

Na+ has more size than Al+++.

so the melting point of Nacl is much higher than that of Alcl3

• Melting Point Nacl

• Nacl Melting Point

• Anonymous
5 years ago

Assuming that you're talking about aqueous solutions of each at the same concentration, then the answer is table sugar. That's a molecular compound, and if you have a 1M solution, there is one mole of sugar molecules present in solution. If you have a 1M solution of KCl, there are two moles of ions in solution (KCl dissociates in solution to give K+ and Cl- ions). For 1M AlCl3, there will be four moles of ions in solution (Al3+ and 3 Cl-). Vapor pressure decreases as the number of solute particles in solution increases (Raoult's law), so the sugar solution, with the smallest concentration of dissolved particles, will have the highest vapor pressure.