Question

how many molecules of ethane c2h6 are present in .257 g of C2H6?
thank you

i got 5.14 x10^21

Answer 1

the molar mass is ... 30.07 g

moles = mass / molar mass

molecules = moles * 6.02E23

Answer 2

so was i correct?
(.257 x 6.023 x 10^23)/ 30.07 = 5.14 x 10^21