Question

How many moles of o are in 15.0 mol fe(no3)3?

Answer 1

N[Fe(NO₃)₃]=15.0 mol

n(O)=3×3×n[Fe(NO₃)₃]=9n[Fe(NO₃)₃]

n(O)=9×15.0=135.0 mol

Answer 2

Answer : The number of moles of oxygen atoms are 135 moles.

Explanation : Given,

Moles of $Fe(NO_3)_3$ = 15.0 mole

The given chemical formula is, $Fe(NO_3)_3$

By the mole concept:

In $Fe(NO_3)_3$, there are 1 mole of iron (Fe) atom, 3 moles of nitrogen (N) atoms and 9 moles of oxygen (O) atoms.

As, 1 mole of $Fe(NO_3)_3$ contains 9 moles of oxygen atoms

So, 15.0 moles of $Fe(NO_3)_3$ contains $15.0\times 9=135$ moles of oxygen atoms.

Hence, the number of moles of oxygen atoms are 135 moles.