We know, molecular mass of sucrose is 342 g/mol.
So, number of moles in 18 g is :
[tex]n_1 = \dfrac{342\ g/mol}{18\ g}\\\\n_1 = 0.053 \ moles[/tex]
Also, number of moles of water is :
[tex]n_2 = \dfrac{180}{18} \\\\n_2 = 10 \ moles[/tex]
We know, 1 mole of sucrose contain 11 moles of oxygen.
So,
[tex]n' = 0.053\times 11\\\\n'= 0.583\ moles[/tex]
1 mole of water contain 1 mole of oxygen .
So, moles of oxygen in water are :
[tex]n'' = 10\ moles[/tex]
Total number of moles, [tex]n' + n'' = 10.583 \ moles[/tex] .
Number of oxygen atoms are :
[tex]N = 6.022 \times 10^{23}\times 10.583\\\\N = 6.37 \times 10^{24}[/tex]
Hence, this is the required solution.
