|An animation that looks at the way carbon
dioxide and other greenhouse gases behave on a molecular level
Greenhouse gases are gases that exist in our atmosphere that contribute to the overall warming effect known as the greenhouse phenomenon. They include water vapor, carbon dioxide, methane, nitrous oxide, ozone, and industrial gases like hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride.
Scientists say that the chemical bonds in greenhouse gases are not as secure as those of gases that have only two molecules, such as nitrogen and oxygen. Nitrogen and oxygen make up far more of our atmosphere than greenhouse gases. But, because they are comparatively stable when they vibrate, they do not send energy scattering off in all directions. Energy generally just passes on through them.
In contrast, greenhouse gases absorb and emit much more energy. The secret to this capacity lies in their chemical bonds. These gases have more than two atoms… atoms that can move in a variety of ways when they are struck by infrared radiation. The capacity of these atoms to vibrate in different ways makes them much better at absorbing energy than their more securely bonded counterparts with two atoms. These molecules don’t hold the energy forever, though, and so energy is eventually sent scattering off in all directions….including right back to earth.
|For more information
After working with this animation, students will be able to explain on a molecular level why certain gases are more efficient than others at capturing radiation.
|Can be used with existing lesson plans on
Greenhouse gases; Earth's atmosphere; greenhouse effect; radiation; solar energy; chemical bonds; molecules; atoms
|Additional ways to use this asset to enrich your curriculum
|Molecules on the Move: Greenhouse Gases (PDF | Word)