Qualitative plots depicting the pH-dependence of the solubility for three compou
ID: 816431 • Letter: Q
Question
Qualitative plots depicting the pH-dependence of the solubility for three compounds are shown below. The three compounds, in no particular order, are magnesium hydroxide (Mg(OH)2), aluminum oxide (Al2O3), and silver chloride (AgCl).
Which one of the following correctly matches each plot with the compound it represents?
AgCl
Al2O3
Mg(OH)2
Mg(OH)2
Al2O3
AgCl
Al2O3
Mg(OH)2
AgCl
Mg(OH)2
AgCl
Al2O3
Al2O3
AgCl
Mg(OH)2
A) A
B) B
C) C
D) D
E) E
AgCl
Al2O3
Mg(OH)2
BMg(OH)2
Al2O3
AgCl
CAl2O3
Mg(OH)2
AgCl
DMg(OH)2
AgCl
Al2O3
EAl2O3
AgCl
Mg(OH)2
Qualitative plots depicting the pH-dependence of the solubility for three compounds are shown below. The three compounds, in no particular order, are magnesium hydroxide (Mg(OH)2), aluminum oxide (Al2O3), and silver chloride (AgCl). Which one of the following correctly matches each plot with the compound it represents?Explanation / Answer
Among the given illustrations -
iilustration:1 represents Mg(OH)2 because , when pH increases basisicity of the solution increases, hence the reaction equilibrium will shift towards right according to Lechatelier principle.
Mg(OH)2 (s) <=======> Mg2+ (aq) + 2 OH- (aq)
illustration:2 represents AgCl, because pH change can't effect the equillibrium.
illustration:3 represents Al2O3 .because -
Al2O3 (s) + H2O (l) <=====> Al(OH)3 (s) <====> Al3+ (aq) + 3 OH- (aq)
Hence, the solubility decreases initially and increases after some time, because Al(OH)3 reacts with OH- and forms Al(OH)4- . Hence -
answer D) is correct