Why physical and chemical properties are found among the nonmetals?

Because the elements they tend to gain electrons to form anions during chemical reactions, they are electronegative elements with high ionization energies, so they are non-lustrous, brittle and poor conductors of heat and electricity. They cannot react to water as its their chemical property due to being unable to break the bond between H and O in water. The non-metals cannot reduce hydrogen by donating electrons.

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: