P-Block Elements Ques 518
Question: In the following sets of reactants which two sets best exhibit the amphoteric characters of
$ Al_2O_3.xH_2O~ $ Set 1: $ Al_2O_3.xH_2O(s)andO{{H}^{-}}(aq) $ Set 2: $ Al_2O_3.xH_2O(s)andH_2O(l) $ Set 3: $ Al_2O_3.xH_2O(s)and{{H}^{+}}(aq) $ Set 4: $ Al_2O_3.xH_2O(s)andNH_3(aq) $
Options:
A) 1 and 2
B) 1 and 3
C) 2 and 4
D) 3 and 4
Show Answer
Answer:
Correct Answer: B
Solution:
Aluminium oxide is amphoteric oxide because it shows the properties of the both acidic and basic oxides. It reacts with both acids and bases to form salt and water. $ Al_2O_3.xH_2O+2NaOH\xrightarrow{{}}NaAlO_2+H_2O $ $ Al_2O_3.xH_2O+HCl\xrightarrow{{}}AlCl_3+H_2O $
