Which term best describes c2o4 2− ? polyatomic anion polyatomic cation monatomic anion monatomic cation

Polyatomic anion

Explanation:

Polyatomic anion:

The polyatomic anion is substance having more than one atoms and carrying negative charge.

The poly is Greek word meaning "many". The given compound C₂O²⁻₄

is polyatomic anion because it is made up of more than one atom and have negative charge. The atoms in this compound act as a single unit. In this compound two carbon atoms combine with four oxygen atoms and oxygen carry -2 charge.

In contrast to polyatomic anion, polyatomic cations are also exist. In polyatomic cations positive charge is present in compound and it is also made up of more than one atoms.

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: