Density= mass/volume
volume=mass/density
volume= 40.0g/1.114g per mL
volume= 35.90664273 mL
volume = 35.9 mL
the element hydrogen atom is made up of oxygen atoms.
The mass of Hydrogen is 2 g/mol
The mass of Helium is 4 g/mol
I'm guessing D or C, remember that the noble gases cannot combine
Http://water.ky.gov/groundwater/Pages/GroundwaterAwareness.aspx
