Question

Write down the formulae of the compound that can be formed from ions

Ions. Valency. Formulae

SO4. 2. ?
Na. 1. ?

Cl. 1
Fe. 3

PO4. 3
Ca. 2

Answer 1

(1) ${Na_2SO_4}$ (Sodium Sulphate)

(2) ${FeCl_3}$ (Iron(III) chloride)

(3) ${Ca_4{(PO_4)}_{2}}$ (Calcium Phosphate)

Answer 2

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