Question

1. Assuming that the formation of an aqueous solution of Al(NO3)3 is obtained by mixing solid Al(OH)3 and aqueous nitric acid . Write a balanced net ionic equation?

       2. Which of the following combination will produce a precipitate?

Pb(NO3)2 (aq) and HCl (aq)

Cu(NO3)2 (aq) and KC2H3O2 (aq)

KOH (aq) and HNO3 (aq)

AgC2H3O2 (aq) and HC2H3O2 (aq)

NaOH (aq) and Sr(NO3)2 (aq)

         3 . In the following reaction, which species is reduced?

Au(s) + 3NO3-(aq) + 6H+(aq) → Au3+(aq) + NO(g) + 3H2O (l)

Answer 1

1. Assuming that the formation of an aqueous solution of Al(NO3)3 is obtained by mixing solid Al(OH)3 and aqueous nitric acid . Write a balanced net ionic equation?

Apply:

Al(OH)3(s) + HNO3(aq) = Al(NO3)3(aq) + H2O(l)

balance

Al(OH)3(s) + 3HNO3(aq) = Al(NO3)3(aq) + 3H2O(l)

ionic:

Al(OH)3(s) + 3H+(aq) --> Al3+(aq) + 3H2O(l)

2. Which of the following combination will produce a precipitate?

Pb(NO3)2 (aq) and HCl (aq) --> PbCl2(s) since chlorides from lad are not souble

Cu(NO3)2 (aq) and KC2H3O2 (aq) --> None, acetate and copper wont precipitate

KOH (aq) and HNO3 (aq) --> No precipitation, this is acid base reaction only

AgC2H3O2 (aq) and HC2H3O2 (aq) --> slightly soluble (Silver acetate)

NaOH (aq) and Sr(NO3)2 (aq) --> Sr(OH)2(s) will precipitate since Transition metals hydroxide are not soluble

3 . In the following reaction, which species is reduced?

Au(s) + 3NO3-(aq) + 6H+(aq) → Au3+(aq) + NO(g) + 3H2O (l)

Reduction --> Specie that GAINS electrons

so..

H goes from +1 to +1 (in H2O)

Au goes from 0 to +3

N goes from +5 to -2, it gains electrons! choose Nitrogen