# finding out fractions of ions(different valencies/charges) of an element in non-stoichiometric compounds

Analysis shows that nickel oxide has the formula $$Ni_{0.98}O_{1.00}$$. What fractions of nickel exist as $$Ni^{2+}$$and $$Ni^{3+}$$?

What i did:

Let the number of $$Ni^{2+}$$ and $$Ni^{3+}$$ atoms be $$x$$ and $$y$$ respectively

one atom/ion of $$Ni^{2+}$$ satisfies one $$O^{2-}$$ atom

$$2 \over 3$$ atom/ion of $$Ni^{3+}$$ one $$O^{2-}$$ atom

and then i wrote down the equations: $$x + 3 \over 2 y =1$$ and $$x+y=0.98$$

Then i solved the equations to get the answers:

$$x=0.94$$ $$and$$ $$y=0.04$$

Is what i did correct? If not then guide me how to solve the question

• i am getting used to mathjax and markdown, so please if my question is tough to read someone edit it Oct 17 '18 at 17:49
• i don't know what is wrong with this question that nobody would answer it. I've given question and also said what my approach was. please someone answer Oct 18 '18 at 3:17

Total negative charge$$= 200$$
Total positive charge$$= 2x+3y$$ where $$x$$ and $$y$$ are what you have assumed to be in the question . Now Net charge =0.Equate the positive and negative charges.
Also $$x+y=98$$. Solve them and you will get the same number. This of course has an high degree of