Answer : Mass of diphosphorous pentoxide will be 1.55 X g.
Explanation : We know that the number of oxygen atoms are, N(O) = 1 X .
So we have to find the mass of () = ?
Now, the number of oxygen atoms is given in atoms so we have to divide it by avogadro's number(Na);
n(O) = N(O) / Na.
On substituting we get, n(O) = 1 / 6.022 X /mol.
We get, n(O) = 1.66 X mol.
We can take from molecular formula of diphosphorus pentoxide:
number of oxygen and phosphorus ratio;
n(O) : n(P) = 2 : 5.
n(P) = 1.66 X mol X 5/ 2.
So the number of phosphorrus will be n(P) = 4.15 X mol.
Now,m(O) =1.66 X mol X 16 g/mol = 2.65 X g.
and,m(P) = 4.15 X mol X 30.97 g/mol = 1.285 X g.
We can conclude that, m(P₂O₅) = m(O) + m(P).
So, m(P₂O₅) = 2.65 X g + 1.285 X g = 1.55 X g.