Question

Lab assistant continues to add sugar
cubes to a container of water until no
more can dissolve. Which action will
cause more sugar to be dissolved?
(Explain you answer
18:28​

Answer 1

Explanation:

Break the Sugar Up

Energy, which is the capacity to do work or produce heat, affects the rate at which a solute will dissolve. Breaking up, crushing or grinding a sugar cube before adding it to water increases the sugar's surface area. The more surface area a solute has, the faster it will dissolve because more particles of the sugar can interact with the water. This means the finer the sugar particles, the faster it will dissolve. The sugar in the middle of a sugar cube is protected from the water by the sugar in the outer layers of the cube; the water has to go through those outer layers first. But if you crush the cube into a powder, all of the sugar is exposed to the water at once.

Stir the Mixture

Stirring, or agitation, helps to disperse the particles of sugar throughout the water, which is another way of increasing the surface area of the sugar and accelerating the time it takes to dissolve. The stirring motion also increases kinetic energy, which increases the temperature of the solution – and that's the next way to make sugar dissolve more quickly.

Heat the Mixture

If you add a sugar cube to a cup of room-temperature water and another sugar cube to a cup of hot water, you'll find that the sugar dissolves faster in the cup of hot water. The sugar particles move around and interact more at higher temperatures because the additional heat adds more energy to the process.