Answer:
5.02×10²⁵ atoms of O
Explanation:
Our compound is: Fe(NO₃)₂
We know that 1 mol of Fe(NO₃)₂ has 1 mol of Iron(II), and 2 moles of nitrates (where you have 2 moles of N and 6 moles of O)
Let's convert the mass to moles and firslty, let's convert the mass from kg to g → 2.500 kg . 1000 g / 1kg = 2500 g
We convert the moles to mass → 2500 g / 179.85 g/mol = 13.90 moles
Now we can propose this rule of three:
1 mol of Fe(NO₃)₂ has 6 moles of O
Then, 13.90 moles of Fe(NO₃)₂ will have (13.90 . 6) /1 = 83.4 moles of O
Let's count the atoms: 83.4 mol . 6.02×10²³atoms /1mol = 5.02×10²⁵ atoms of O