A
Fe²⁺
ijzer(II)ion / ijzer(2+)ion
A_r = 55,9

B
NO₃^-
nitraation
M_r = 62,0 = 14,0 + 3 x 16,0

C
NH₄⁺
ammoniumion
M_r = 18,0 = 14,0 + 4 x 1,0

D
PO₄^3-
fosfaation
M_r = 95,0 = 31,0 + 4 x 16,0

E
S^2-
sulfide-ion
A_r = 32,1