Answer:
0.500979
Explanation:
To determine the number of moles, take a look at the following formula and substitute known values -
Moles = Mass / Molar Mass,
Moles = 40.10 grams / 80.0432 grams / mole
as you can see, 40.10 / 80.0432 = ( About ) 0.500979, which is option B
Hope that helps!