Question

Add the physical state for each substance in the following aqueous reactions. Then write and balance a net ionic equation for each reaction.

(a)	Cr2(SO4)3	+	KOH	→	Cr(OH)3	+	K2SO4
	(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)
	AP 17
(b)	K2CrO4	+	PbCl2	→	KCl	+	PbCrO4
	(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)
	AP 34
(c)	Na2SO3	+	H2SO4	→	Na2SO4	+	H2O	+	SO2
	(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)		(aq)    (s)    (g)    (l)
	AP 55

Answer 1

In order to know the state of the compounds, you will need to know the Ksp of the products. The one with the smallest value will be the one to precipitate, and it will have the solid state. I already look for the Ksp in my text book, so I'm gonna put directly the state. If you want me to put those values, please tell me.

a) Cr₂(SO₄)_3(aq) + 6KOH_(aq) ---------->2Cr(OH)_3(s) + 3K₂SO_4(aq)

Ion equation: 2Cr⁺³_(aq) + 3SO₄^2-_(aq) + 6K⁺_(aq) + 6OH^-_(aq) ----------> 2Cr(OH)_3(s) + 6K⁺_(aq) + 3SO₄^2-_(aq)

net equation: 2Cr⁺³_(aq) + 6OH^-_(aq) ----------> 2Cr(OH)_3(s)

b) K₂CrO_4(aq) + PbCl_2(aq) ---------> 2KCl_(aq) + PbCrO_4(s)

Ion equation: 2K⁺_(aq) + CrO₄^2-_(aq) + Pb²⁺_(aq) + 2Cl^-_(aq) -----------> 2K⁺_(aq) + 2Cl^-_(aq) + PbCrO_4(s)

Net equation:CrO₄^2-_(aq) + Pb²⁺_(aq) -----------> PbCrO_4(s)

c) Na₂SO_3(aq) + H₂SO_4(aq) -----------> Na₂SO_4(aq) + H₂O_(l) + SO_2(g)

Ion equation: 2Na⁺ + SO₃^2- + 2H⁺ + SO₄^2- ------------> 2Na⁺ + SO₄^2- + H₂O(l) + SO_2(g)

Net equation: SO₃^2- + 2H⁺------------> H₂O(l) + SO_2(g)

_{Hope this helps}