Another question sent to sean@simplechemconcepts by ‘Student X’ to be shared with all “chemists”. Go work it out!
“If you don’t practice it, You Loose It”
– Sean Chua
When a colourless solution S was added to aqueous sodium hydroxide, no visible change was observed. When aluminum powder was added, a pungent gas which gave a brown precipitate when bubbled into aqueous iron (III) chloride was obtained. What ions could be present in S?
- A. Na+ , NH4+
- B. K+ , NO3-
- C. Na+ , Br-
- D. Ca2+ , NO3-
Student X’s suggested answers:
What I think: B and D is out as a white ppt is formed with aq NaOH. Hence, either A and C. But I don’t know which one to choose between the two.
PS: Check out “Comments” below for suggested answers.
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