Air is a poor conductor of heat. The air trapped between the two panes is a pretty good <em>insulator</em>. It does a lot to prevent heat from flowing through the windows ... keeping heat IN during the Winter, and OUT during the Summer.
Answer:
Diffusion is the movement of a molecule from an area where the molecule is in high concentration to an area where the molecule is in low concentration. Facilitated diffusion is the movement of a molecule from an area of high concentration to an area where the molecule is in low concentration. Osmosis is the diffusion (high to low concentration) of water through a semi-permeable membrane. Water moves from an area of high water molecule concentration (and lower solute concentration) to an area of low concentration (and higher solute concentration.
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