Ionic vs Covalent Showdown
Rank substances by melting point — ionic beats covalent.
Setting up the bench…
What this lesson covers
Why it matters
Drop sugar and salt on the same hot pan. The sugar melts and chars quickly; the salt just sits there, needing a furnace to melt.
Predict first
Which usually has the higher melting point?
Ionic lattices need huge energy to break, so ionic solids melt very high. Covalent molecular substances are held by weak forces between molecules, so they melt low.
- An ionic compound — correct
- A covalent molecular compound
- They are always equal
What you do
Rank these by melting point, highest first.
Check yourself
Covalent molecular substances melt easily because…
The weak intermolecular forces take little energy to overcome.
A substance melts at about 2800°C. It is most likely…
Only giant ionic (or giant covalent) structures melt that high.
- only weak forces act between their molecules — correct
- their atoms are extremely tiny
- they contain no bonds at all
- ionic — correct
- covalent molecular
- a gas at room temperature