Answer
6.69$\times10^{21}$ molecules.
Work Step by Step
Mass in grams = 0.334g
Molar mass = 2 (12.011g) + 6(1.008g)
Number of moles = mass in grams/molar mass.
Number of molecules = No of moles$\times N_{A}$
No of molecules= $\frac{0.334g}{30.07gmol^{-1}}\times 6.022\times10^{23}\approx6.69\times10^{21}$
