Nitrogen Oxides Comparison Table

Property	$N_{2}O$	NO	$N_{2}O$ _{3}	$NO_{2}$	$N_{2}O$ _{5}
Oxidation State of N	+1	+2	+3	+4	+5
Nature	Neutral	Neutral	Acidic	Acidic	Acidic
Colour	Colourless	Colourless	Blue (liquid/solid)	Brown/reddish	Colourless solid
Paramagnetic?	No	Yes (odd $e^{-}$ )	No	Yes (odd $e^{-}$ )	No
Anhydride of	—	—	H $NO_{2}$	—	$HNO_{3}$
Common name	Laughing gas	Nitric oxide	Dinitrogen trioxide	Nitrogen dioxide	Dinitrogen pentoxide
Notable reaction	Supports combustion	Toxic; binds Hb	$N_{2}O$ _{3} + $H_{2}O$ → 2H $NO_{2}$	Dimerises to $N_{2}O$ _{4}	$N_{2}O$ _{5} + $H_{2}O$ → 2 $HNO_{3}$

Trend Notes:

Oxidation state increases: +1 → +2 → +3 → +4 → +5 (mnemonic: "Naughty Newborns Never Nap Daily")
Neutral oxides: $N_{2}O$ (+1) and NO (+2) only
Acidic oxides: all from +3 onwards
Paramagnetic (odd electron): NO and $NO_{2}$ only