Why?

* Solubility: Sugar is highly soluble in water, meaning it dissolves readily. Coffee, on the other hand, is a complex mixture of compounds, including some that are less soluble in water.

* Temperature: Hot water has more energy than cold water, which increases the rate at which molecules move and interact. This enhanced movement allows sugar molecules to break apart and disperse more readily in the water.

* Coffee Compounds: Coffee contains compounds like tannins and oils that are less soluble in water. These compounds require higher temperatures and agitation to dissolve properly.

In conclusion, sugar's higher solubility and the increased energy of hot water contribute to its faster dissolution compared to coffee.