The passivity of iron in concentrated nitric acid is due to
ferric nitrate coating on the metal
ammonium nitrate coating on the metal
a thin oxide layer coating on the metal
a hydride coating on the metal
C.
a thin oxide layer coating on the metal
When iron reacts with concentrated HNO3, a thin oxide layer is formed on the metal surface. So, iron becomes passive.
Phosgene is common name of
carbon dioxide and phosphene
phosphoryl chloride
carbonyl chloride
carbon tetrachloride
A deep brown gas is formed by mixing two colourless gases which are
NO2 and O2
N2O and NO
NO and O2
NH3 and HCl