online lesson, chemical bonding by anthony low(25)

Harmless element: nitrogen
Harmless element: oxygen
Oxygen (O) + nitrogen (N) = nitrous oxide. (N2O). Covalent bonding is taking place when the 2 elements bond together. It is because it is between two non-metallic elements.
Introduction to the elements
Nitrogen: elemental nitrogen is a harmless gas that is colorless, odorless and tasteless. It consist 78.08% by volume of Earth's atmosphere. Nitrogen is needed in plants to make protein from pure carbohydrate. If plants don’t have nitrogen, they can’t survive and when plants can’t survive, human will not exist anymore.
Source: http://en.wikipedia.org/wiki/Nitrogen
http://wiki.answers.com/Q/How_do_plants_use_nitrogen
Oxygen: oxygen gas consists about 20% of Earth’s atmosphere. It is one that human cannot live without. We need it for respiration round the clock. The ozone layer is made up of oxygen which protects the earth from the ultraviolet radiations of the sun. Without the ozone layer, Earth would become very hot. So oxygen is also definitely not a harmful element and it is very useful for human etc…
Source: http://en.wikipedia.org/wiki/Oxygen
http://www.blurtit.com/q304435.html
Nitrous Oxide
However, Sustain level of nitrous oxide can be very harmful to your body like tissue damages etc... Also, when nitrous oxide react with the rain when lightning strikes, it forms acid rain. Acid rain will destroy lots of buildings and structures and it is also not good for humans as it will also destroy crops. It is ranked third behind carbon dioxide and methane in contributing to global warming.
Source: http://www.triplepundit.com/2010/04/nitrous-oxides- global-warming-impact-no-laughing-matter
http://en.wikipedia.org/wiki/Nitric_oxide
Formation of nitrous oxide
It can be made my 2 ways:
• Human-made:
Agricultural soils are by far the biggest source. Some of the nitrogen can end up being emitted as N2O through the processes of nitrification and denitrification. Globally, between 2 and 4 million tonnes of N2O-N are thought to be released into the atmosphere each year via this pathway.
• Natural:
Temperate and tropical soils, with the world's oceans also being an important contributor. Total annual emissions of N2O from natural sources are estimated to be about 10 million tonnes.
Sources: http://www.eoearth.org/article/Nitrous_oxide
http://www.triplepundit.com/2010/04/nitrous-oxides-global-warming-impact-no-laughing-matter