In: Chemistry
mass of glucose = 126 mg = 0.126 g
molar mass of glucose = 180 g / mole
moles of glucose = mass / molar mass
= 0.126 g / 180 g / mol
= 7.0 x 10^-4
number of molecules = moles x avagadro number
= 7.0 x 10^-4 x 6.023 x 10^23
= 4.22 x 10^20
number of molecules = 4.22 x 10^20