2 Points
Put these events in order, with the most recent event appearing at the top of
your list
T! A nuclear-powered submarine is developed.
11 A nuclear chain reaction is created by Enrico Fermi.
T1 The idea of a fusion bomb is tested.
11 At the end of World War II, atomic bombs are dropped on Japan.
ti Atoms of uranium are split.
SUBMIT

the grams   of   barium that   are in   2.3 x 10^23   atoms of barium   is   52.4 g (answer c)

    calculation

mass = moles   of ba   x molar   mass of ba

  molar mass of ba from periodic table=   137.3 g/mol

  use the   avogadro's law   constant   to   calculate the moles of barium

  that   is     1 mole =   6.02   x 10^23 atoms

                    ? moles = 2.3 x 10^23   atoms

by cross   multiplication

=(1 mole   x 2.3x 10^23 atoms)   / 6.02   x10^23 atoms)=   0.382   moles

mass   is therefore = 137.3   g/mol x 0.382 mol = 52.4 ( answer c)

explanation:

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.