Answer:
1.34×10²³ molecules of C₆H₆
Explanation:
Firs ot all we need to the determine the amount of benzene, in 17.4 grams of it.
Molar mass from benzene = 78 g/mol
Let's convert the grams to mol → 17.4 g . 1mol / 78 g = 0.223 moles
We know, that 1 mol of anything contains the Avogadro's Number, 6.02×10²³ particles. Let's count the molecules
1 mol of benzene has NA molecules
Therefore 0.223 moles must have (0.223 . 6.02×10²³) / 1 = 1.34×10²³ molecules of benzene