Problem

Two oxides of nitrogen,

NO

and

NO_{2}

are allowed to react together at

243^{\circ}K

and form a coloured compound of nitrogen (

X

). When compound (

X

) reacts with water to yield another compound of nitrogen (

Y

). The shape of the anion of (

Y

) molecule is : a. triangular planar b. triangular pyramidal c. tetrahedron d. square planar