--------- is a powerful oxidising agent.

A metal which reacts with dilute nitric acid is

Con. HNO₃ gives ________ fumes on heating.

Which one becomes passive in concentrated nitric acid?

Con. HNO₃ prepared in laboratory is

The conversion of free atmospheric _________ into useful nitrogenous compounds in the soil is known as fixation of atmospheric nitrogen.

The gaseous reactants used during Ostwald's process are