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Which best defines nitrogen fixation?
the process of creating free nitrogen for plants to absorb
the breakdown of nitrogen in the soil
the conversion of nitrogen gas into a usable form
the destruction of the bonds between nitrogen and other elements

Nitrogen is converted from atmospheric nitrogen (N2) into usable forms, such as NO2-, in a process known as fixation.

In this case, the answer which best describes nitrogen fixation, is the third option, the conversion of nitrogen gas into a usable form.

answer; /// i do believe that the correct answer is (a) boiling

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.