- #1
Kyoma
- 97
- 0
Problem:
When a colourless solution S was added to aqueous sodium hydroxide, no visible change was seen. When aluminium powder was added, a pungent gas which gave brown precipitate when bubbled into aqueous iron(III) chloride was obtained. What ions could be present in S?
(a) Na+, SO42-
(b) K+, NO3-
(c) Na+, Br-
(d) Ca2+, NO3-
Attempts:
The answer is (b), but I have no idea how to arrive at the answer. I was thinking about ammonium ions since ammonia (pungent gas) would be produced when sodium hydroxide and aluminium were added to ammonium ions, but there was no answer. I simply do not understand.
When a colourless solution S was added to aqueous sodium hydroxide, no visible change was seen. When aluminium powder was added, a pungent gas which gave brown precipitate when bubbled into aqueous iron(III) chloride was obtained. What ions could be present in S?
(a) Na+, SO42-
(b) K+, NO3-
(c) Na+, Br-
(d) Ca2+, NO3-
Attempts:
The answer is (b), but I have no idea how to arrive at the answer. I was thinking about ammonium ions since ammonia (pungent gas) would be produced when sodium hydroxide and aluminium were added to ammonium ions, but there was no answer. I simply do not understand.