A mother finds her daughter’s mug of hot cocoa on a table an hour after she had been drinking it. As the mother pours out the cocoa, she sees brown solids in the bottom of the mug. How can this be explained?(1 point)

Question

Responses

The cocoa was mixed with hot water, but some cocoa settled as it cooled because the solubility went down.
The cocoa was mixed with hot water, but some cocoa settled as it cooled because the solubility went down.

All dissolved substances will come out of solution over time. If the mother waits long enough, then all of the powder will appear at the bottom of the mug.
All dissolved substances will come out of solution over time. If the mother waits long enough, then all of the powder will appear at the bottom of the mug.

This would only happen if too much cocoa powder was added in the first place, because the solubility should not change.
This would only happen if too much cocoa powder was added in the first place, because the solubility should not change.

The cocoa was mixed with hot water, but some cocoa settled as it cooled because the solubility went up.

Answer 1

The best explanation for the observed phenomenon is:

The cocoa was mixed with hot water, but some cocoa settled as it cooled because the solubility went down.

When the hot cocoa was initially made, cocoa powder dissolved well in the hot water due to higher solubility at elevated temperatures. However, as the cocoa cooled down, the solubility of the cocoa powder decreased, causing some of it to precipitate out and settle to the bottom of the mug.