2 N O 2 - + O 2 → 2 N O 3 - This step of nitrification is done by ________bacteria.

Step-by-step solution

The process of conversion of nitrogen N 2 to ammonia is termed as nitrogen fixation. Most of the ammonia is converted to nitrate by soil bacteria, where ammonia is first oxidized to nitrite by the bacteria Nitrosomonas or Nitrococcus . The nitrite is further oxidized to nitrate with the help of Nitrobacter. These steps are called nitrification and the nitrifying bacteria are called chemoautotrophs.