JAMB - Chemistry (1990 - No. 10)
The brown fumes given off when trioxonitrate (V) acid is heated consist of ?
NO2 and O2
H2O and NO2
NO2' O2 and H2O
NO, NO2 and H2O
Selitys
decomposition of the acid by heat to produce reddish-brown gas (nitrogen (iv)) which then dissolve in the acid to impart the yellow colour.