<u>Answer:</u> Silver has 47 electrons, 47 protons and 43 neutrons. Barium has 56 electrons, 56 protons and 76 neutrons.
<u>Explanation:</u>
Atomic number is defined as the number of protons or electrons that are present in a neutral atom.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
Atomic number = 47
Mass number = 90
Atomic number = Number of protons = Number of electrons = 47
Number of neutrons = Mass number - Atomic number = 90 - 47 = 43
Hence, silver has 47 electrons, 47 protons and 43 neutrons.
Atomic number = 56
Mass number = 132
Atomic number = Number of protons = Number of electrons = 56
Number of neutrons = Mass number - Atomic number = 132 - 56 = 76
Hence, barium has 56 electrons, 56 protons and 76 neutrons.