35 The weighted average of the masses of the isotopes of an element
а.
b.
mass number
isotope
C
d.
atomic number
atomic mass
12
Mass number
(#protons plus
#neutrons)
***
Atomic number
(#protons)
12.011 Atomic weight

American scientist, linus pauling, was one of many scientists racing to discover the molecular structure of dna. pauling initially thought that the molecule was a triple helix. later, james watson and francis crick unveiled their double helix model, which turned out to be an accurate description of the molecule's shape. why did watson and crick succeed when pauling failed?