Question

How many g of oxygen are in 4.50x1024 molecules of P205?0 43.9 gO 4.24x1022 gO 600 gO 598 g

Answer 1

If we have 4.50 x 10²⁴ molecules of P₂O₅, we will have 5 times as much atoms of oxygen, because in each molecule of P₂O₅ there are 5 atoms of oxygen.

So, the number of atoms of oxygenm in total, is:

`5\cdot4.50*10^(24)=22.5*10^(24)=2.25*10^(25)`

The atomic mass of oxygen is approximately 15.9994 g/mol. So, we first need to convert the number of oxygen atoms for number of moles of oxygen.

To do that, we divide the number of atomx of oxygen by Avogadro's Numver:

`N_A\approx6.022*10^(23)mol^(-1)`

So, we have:

`n_O=(2.25*10^(25))/(6.022*10^(23)mol^(-1))=37.36300\ldots mol^{}`

Now, we can convert to mass:

`\begin{gathered} M_O=(m_O)/(n_O) \\ m_O=M_O\cdot n_O=15.9994g/mol\cdot37.36300\ldots mol=597.7856\ldots g\approx598g \end{gathered}`

So, we have approximately 598 g of oxygen atom.