Which of the following is the best definition of radioactive decay?
O
A. Radioactive decay is the loss of mass that occurs when an atom
is formed.
) B. Radioactive decay is the splitting of a nucleus
amounts of energy.
O
C. Radioactive decay is the release of energy resulting from a
chemical reaction.
O
D. Radioactive decay is the spontaneous breakdown of a nucleus into
smaller parts.

Radioactive decay is the spontaneous breakdown of a nucleus into smaller parts

Explanation:

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: