Answer:1.309 x 10^24 oxygen atoms
Explanation:
Molar mass of N2O4,= 2 x Molar mass of Nitrogen + 4 x Molar mass of Oxygen
= 2 x 14.01 + 4 x 16.0
= 92.02 g/mol
One mole of a substance is equal to 6.022 × 10²³ unit/ atoms/ molecules
In N2O4, there are 4 moles of Oxygen
if 92.02 g contains = 4 x 6.022 x 10 ^23 molecules
50.0 g wll contain= (4 x 6.022 x 10 ^23 x 50)/ 92.02g
1.309 x 10^24 oxygen atoms