>Hydrogen has approximately twice the lifting power of He. Hydrogen has an
>atomic weight of approximately 1, while He has an atomic weight of about 4.
>However, hydrogen forms diatomic bonds to become H2 molecules with a
>molecular weight of about 2.
>
>The rule of thumb I use for He is one cu ft lifts approx 1 oz. H2 would
>lift approx 2 oz per cu ft. =20
Sorry I do not agree with some of the above statements. "Lifting power" is
not proportional to the molecular weight of the gas in the balloon but to
the difference between the "molecular weight" of the air (around 29) and
that of the gas in the balloon. Then (29-2)/(29-4)~ 1.08 means that hidrogen
has about 8% more basic lifting power than helium. If you take in account
the dead weight of the balloon this can improve the "net lifting power"
relation but not to the extent indicated, unless you use ballons with a
weight abnormally high.
Basic lifting power for hydrogen at 0=BAC is around 1.2 Kg/cubic meter and=
at
25=BAC about 1.1 Kg/cubic meter. If the balloon has a volume V (in cubic
meters) the net lifting power would be around (1.1 V- weight of the balloon
in kg)
73s
Jos=E9
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