What factors might lead to a positive nitrogen balance?

nitrogen fixing bacteria fix or attach atmospheric nitrogen in soil or make it easily avialable to the plants as plants need nitrogen as one of their macronutrient element for their growth.

yes

Certain plants (notably legumes - beans) and many bacteria act as nitrogen fixing agents, taking nitrogen from the air and producing nitrogen compounds by combining nitrogen with other elements. Nitrogen fixation can also occur as a result of lightning and some human activities, such as combustion.

Other than that, it stays in the atmosphere, and fixed nitrogen eventually returns to the atmosphere, as well, to begin the cycle again.

There is one atom in nitrogen

there is not one atom of nitrogen, there is one molecule of nitrogen.

There is 6.02 * 10^23 atoms in 1 mole of nitrogen.

Or simply the natural state of nitrogen is n2. or two nitrogen atoms to a molecule. =]

Firstly, N2 is treated sometimes as an inert gas as it is used to create an inert atmosphere so that no reactions take place. But nitrogen has many compounds as it is more chemically reactive than helium or any other inert gases. Its compounds: e.g. Ammonia, Nitric Acid etc. More on: http://en.wikipedia.org/wiki/Nitrogen

It has to be cooled to below -196 degrees Celsius or -321 degrees Fahrenheit.

Lithium is altogether a bigger element than hydrogen. Hydrogen is the smallest element, and lithium is listed later on the periodic table, so lithium's radius is just plain bigger than hydrogen.

Antoine Coefficients for Nitric acid are

A=6.6368

B=1.406

C= -52.15

range 274/376 (K)

reference :- Vapour Pressure and Antoine Constants for Nitrogen Containing compounds

Of Course. It is listed on every periodic table you could look up. Also, for those of you paying any attention in physics, there is a multitude of Nitrogen in the Atmosphere.

Nitrogen makes up approximately 78% of the air you are breathing now.

It took 300 thousand years after the big bang for the Universe to cool enough to create atoms; hydrogen and helium formed first. Nitrogen was formed in the stars through the process of nucleosynthesis. When a star's helium mass becomes great enough to reach the necessary pressure and temperature, helium begins to fuse into still heavier elements, including nitrogen.

It gains three, loses five, or shares pairs of electrons

The nitrogen gas molecule is inorganic.

Organic molecules are compounds that contain carbon and hydrogen with specific bonding. Thus, while CO2 is not organic, CH2O is. By looking at your a nitrogen compound and seeing what other elements are present and how those elements are bound you can determine whether or not it is organic.

diazotrophs.

Water pollution affects the nitrogen cycle the least. The nitrogen cycle is the cycle of nitrogen as it enters earth, becomes fixed, and leaves earth, back to the atmosphere. The only way that water pollution can affect the nitrogen cycle is if there is too much trash in one area of a body of water, thus clogging the surface and not allowing algae to absorb the nitrogen. It could also clog the surface and not allow denitrifying bacteria in waterlogged soil to release the nitrogen back into the atmosphere.

Nitrogen is found in 78% of Earth's air and 3% of Mar's atmosphere.

The chemical symbol for Nitrogen is N. N2

2. Nitrogen in the atmosphere here on Earth is considered diatomic.

This temperature is - 210 0C.

This is a non-existent chemical. There are no nitrogen sulphates, either synthetic or naturally occurring. This is further verified by the 2014 Combined Chemical Dictionary which does not list it.

Two major ways whereby nitrogen is fixed in ecosystems are through rainfall and through leguminous crops.

It goes back into the soil.