How much mass does 0.5 mole of barium contain?

b..

is the correct one

explanation:

covalent bonds form as valence electrons are shared between two atoms. lewis structures and structural formulas are common ways of showing the covalent bonding in organic molecules. formal charge describes the changes in the number of valence electrons as an atom becomes bonded into a molecule.

the answer for sodium is 0.186

the answer for rubidium is 0.251

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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