This help with this chart

Answer:
Explanation:
Atomic mass is the sum of number of protons and neutrons while atomic number is the number of protons or electrons.
A neutral atom has equal number of protons and electrons that's why atomic number could be either number of protons or electrons.
Element Symbol Atomic# Mass# Protons Neutrons
Mercury Hg 80 200 80 120
Solution:
number of neutrons = mass number - atomic number
number of neutrons = 200 - 80
number of neutrons = 120
Element Symbol Atomic# Mass# Protons Neutrons
Tungsten W 74 184 74 110
Solution:
number of neutrons = mass number - atomic number
number of neutrons = 184 - 74
number of neutrons = 110
Element Symbol Atomic# Mass# Protons Neutrons
Sodium Na 11 23 11 12
Solution:
number of neutrons = mass number - atomic number
number of neutrons = 23 - 11
number of neutrons = 12
Element Symbol Atomic# Mass# Protons Neutrons
Antimony Sb 51 122 51 71
Solution:
number of neutrons = mass number - atomic number
number of neutrons = 122 - 51
number of neutrons = 71
Element Symbol Atomic# Mass# Protons Neutrons
Silver Ag 47 108 47 61
Solution:
number of neutrons = mass number - atomic number
number of neutrons = 108 - 47
number of neutrons = 61