Na has a one proton over than electrons.so Na makes a Na+
Cl has a one electron overthan protons.so Cl makes a Cl-
proton has a + affectation
electron has a - affectation ..
Answer: Ta is Tantalum, Os is Osmium and Rh is Rhodium
Explanation: All of these elements are in the transition metal group. Ta is part of the early transition metals while Os and Rh belongs to the late transition metals.