Answer:
1.67×10^25 molecules
Explanation:
No of molecules = no of moles × Avogadros number
No of moles= mass in gram / molar mass
No of moles of water in given sample = 500.3/18
= 27.79 moles
No of molecules = 27.79× 6.02×10^ 23
= 167.32×10^23 or 1.67×10^25
