Formula of nickel oxide with metal deficiency defect in its crystal is Ni _ 0.98 O . The crystal contains Ni ²⁺ and Ni ³⁺ ions. The fraction of nickel existing as Ni ²⁺ ions in the crystal is

Step-by-step solution

Let, in the given crystal Ni _ 0.98 O Ni ²⁺= x and Ni ³⁺=0.98- x Total charge on M ²⁺ and M ³⁺ aligned & =(+2) x +(+3)(0.98- x ) & =2 x +2.94-3 x & =2.94- x aligned As metal oxide is neutral. Therefore, total charge on cations = total charge on anions. aligned 2.94- x & =2 [ Charge of oxygen atom =-2] x & =2.94-2=0.94 aligned So, the fraction of Ni ²⁺ ions in the crystal = 0.94 0.98 =0.96