G5 Rates of Dissolving 02
Another mistake she made was first pouring the tea over ice. The ice is making the solvent cold. She would have been much better off starting with warm tea. Temperature is also a factor in how fast a solute dissolves. The warmer the solvent, the faster the solute will dissolve.

There is yet another way to make solutes dissolve more quickly. At least your sister is using granulated sugar. A sugar cube that has less surface would have taken even more time to dissolve. Smaller particles have greater surface area. Think of a large cake covered with icing. As you cut the cake into pieces, you expose areas that have no icing. With each cut, the more sides without icing you will see.
The same thing happens with sugar. Granulated will dissolve more quickly than the cubes of sugar. Granulated sugar has a greater surface area than a single sugar cube. It provides more points of contact between the solvent and solute.
You look over and see your sister still slowly stirring her cold tea. You can clearly see the sugar sitting on the bottom of the glass. Do you dare tell her she should stir more quickly? Maybe you could explain how she could start with warm tea. A discussion about surface area would surely not go well. Perhaps this is a time for a quick retreat. “Have a great day!” you say as you get up from the table.