Question

state the observation you would make on adding sodium hydroxide
to aqueous solution of

a) ferrous sulphate
b) aluminium chloride​

Answer 1

a. 2Na(OH)2 + FeSO4 > Na2SO4 + FeO2 + 2H2O

b. 2NaOH + Al2Cl3 > Na2Cl3 + Al2(OH)2 [sodium chloride + aluminium hydroxide]

hope it's right answer.

Answer 2

(a). When sodium hydroxide is added to the aqueous solution of Ferrous sulphate , green colour is appeared due to the formation of ferrous hydroxide.

The balanced chemical equation is -

FeSO $_{4}$ + 2 NaOH  ⟶   Fe(OH)$_{2}$  ↓ + Na$_{2}$ SO $_{4}$

(b). When sodium hydroxide is added to the aqueous solution of Ammonium Chloride , the formation of NH$_{3}$ (Ammonia) , NaCl (Sodium Chloride) and H$_{2}$O (water) takes place . Ammonia gas liberates in this reaction .

The balanced chemical equation is -

NH$_{4}$Cl + NaOH  →  NH$_{3}$ + H$_{2}$O + NaCl

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