Which of the following apply to diffusion. select all that apply. solids can diffuse in liquids. liquids can diffuse in liquids. it is the process of intermingling atoms from one substance into another. gas molecules are very close together and diffuse slowly. a solid cannot diffuse in to another solid.

Correct answers are:

Solids can diffuse in liquids. Think of a sugar cube sitting at the bottom of a cup of tea. Liquids can diffuse in liquids. Think of a drop of food colouring in water It is the process of intermingling atoms from one substance into another.

The other answers are incorrect because:

Gas molecules are far apart and diffuse rapidly.  A solid can diffuse into another solid. Pure lead can diffuse into gold, and pure gold can diffuse into lead.