Urea is a very important nitrogenous fertilizer. Its formula is CON2H4 . calculate the percentage of nitrogen in urea.

Calculate the percentage composition of C2H5OH.

List three important nitrogen containing fertilizers.

Calculate the oxidation state of nitrogen ( N ) in NO2

Calculate the oxidation state of nitrogen ( N ) in (NO2)-

Calculate the oxidation number of nitrogen (N) in N2H4

Calculate the oxidation number of nitrogen (N) in N2O5

Give the empirical formula of N2H4

Give the empirical formula of C2H4

Calculate the molecular mass of H2SO4

The mineral spinel has the moleculr formula Mg Al_2O_4 . In this oxide ions are present in ccp arrangement, Mg^(2+) ions occupy the tetrahedral voids while Al^(3+) ions occupy the octahedral voids. Calculate the percentage of tetrahedral voids occupied by Mg^(2+) ions.