Question

how many moles are present in 1.51 x 10^23 molecules of HCl?

Answer 1

 TO convert the number of molecules of a compound to moles, the conversion factor is Avogadro's number, 6.022 x10^23 molecules / mol. We are given with 1.51x10^23 molecules of HCl. We divide the number of moles to Avogadro's number, the number of moles equivalent is 0.25 moles.