Why Does Water in a Boiling Container Not Boil?

[jlaugh87]

Homework Statement

If you suspend an open-topped container of water in a pot of boiling water, water in the inner container will reach 100 degrees C but will not boil. Why is this?

Homework Equations

The Attempt at a Solution

 

[HallsofIvy]

Darned if I know! The question, as stated, makes no sense to me. The water in the open-topped container will eventually just mix with the other water, reach 100 degrees C and boil! Are there time constraints on this? Are you assuming that the heat causing the water in the pot is removed? In that case I suppose there are some conditions on the comparative size of the two containers and original temperature of the water in the container to allow the latent heat in the pot to cause an average temperature of 100 degrees for all the water but not sufficient additional heat to make up the 'heat of boiling' for all the water. But I don't think that's what's meant here.