If the bonds are held together tightly, as an ionic bond or even a covalent bond, there will need to be a strong force to separate those bonds. This would by why their would be a high melting point. Another reason would be re-activity. <span />
Chemical compounds<span> tend to </span>dissolve more quickly in hot solvent than in cold solvent, t<span>he </span>solvent<span> molecules have </span>more<span> energy to pull the solute particles apart. Give an example of two liquids that are miscible.
https://www.studyblue.com/notes/note/n/chemistry/deck/938054
</span>
Answer : The crown is not made of pure (100%) gold.
Explanation :
Formula used :

where,
= apparent weight of the crown in water = 4.50 N
= actual weight = 5.00 N
= density of water = 
= density of crown = ?
Now put all the given values in the above formula, we get:


Density of crown < Density of gold

Thus, the crown is not made of pure (100%) gold.
b............................................