Here's why:

* Solubility: Salt is more soluble in water than sugar. This means that a greater amount of salt can dissolve in a given amount of water compared to sugar.

* Polarity: Both salt and sugar are polar molecules, meaning they have a positive and negative end. This allows them to interact with water molecules, which are also polar. However, salt is a highly ionic compound, with strong electrostatic interactions between its ions. These interactions are stronger than the interactions between sugar molecules and water.

* Crystal Structure: Salt has a simple cubic crystal structure, which allows for easier separation and dissolution of its ions. Sugar, on the other hand, has a more complex, larger molecular structure, making it harder to break apart.

In summary:

Salt's higher solubility, stronger ionic interactions, and simpler crystal structure contribute to its faster dissolution rate in water compared to sugar.