Aradioactive nuclide is used to detect eye tumors. an atom of this radionuclide contains 15 protons, 15 electrons, and 17 neutrons. which is symbol of this radionuclide?

Explanation:- Atomic number is the number of protons or the number of electrons.

Mass number is the sum of number of protons and number of neutrons.

Atomic number = number of electrons= number of protons = 15

Mass number = number of protons + number of neutrons= 15+17= 32.

The representation of element is :

where Z= atomic number, A= mass number , X= chemical symbol of element

The representation of the element with atomic number 15 and mass number 32 is :  

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:

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.