Answer
$0.77\ g$
Work Step by Step
Volume:
$3.00\ m^2\times 250\times 0.60\times10^{-9}\ m=4.5\times10^{-7}\ m^3=0.45\ cm^3$
Mass:
$0.45\ cm^3\times 1.0\ g/cm^3=0.45\ g$
Number of moles of the monomer equals the number of moles of $(CH_2)_2SiCl_2$:
$0.45\ g\div 74.15\ g/mol=6.07\ mmol$
Mass of $(CH_2)_2SiCl_2$:
$6.07\ mmol\times 127.04\ g/mol=0.771\ g$
