if a colorless liquid with a pungent odour is added slowly to another colourless liquid a dark brown precipitate us produced that later dissolves to produce a colorless solution.what are the two colourless liquid
Answers
Answer:
Question
Bookmark
The following table shows the test a student performed on four different aqueous solution which are X, Y, Z and W. Based on the observations provided, identify the action present.
Chemical test Observation Conclusion
To solution X, ammonium hydroxide is added in minimum quantity first and then in excess. A dirty white precipitate is formed which dissolves in excess to form a clear solution.
To solution Y ammonium hydroxide is added in minimum quantity first and then in excess. A pale blue precipitate is formed which dissolves in excess to form a clear inky blue solution.
To solution W a small quantity of sodium hydroxide solution hydroxide solution is added and then in excess. A white precipitate is formed which remains insoluble.
To a salt Z calcium hydroxide solution is added and then heated. A pungent smelling gas turning moist red litmus paper blue is obtained.
Hard
Solution
verified
Verified by Toppr
(i) The conclusion is Zn
2+
ion is present. When NH
4
OH solution is added to ZnSO
4
we get white precipitate of Zn(OH)
2
.
ZnSO
4
+2NH
4
OH→(NH
4
)
2
SO
4
+Zn(OH)
2
These white ppt dissolve in excess of NH
4
OH solution.
Zn(OH)
2
+2(NH
4
)
2
SO
4
+2NH
4
OH→[Zn(NH
3
)
4
]SO
4
+4H
2
O
(ii)The conclusion is Cu
2+
ion is present. The solution Y is copper sulphate solution. With NH
4
OH solution it gives pale blue precipitate of Cu(OH)
2
.
CuSO
4
+2NH
4
OH→(NH
4
)
2
SO
4
+Cu(OH)
2
With excess NH
4
OH solution this solution turns deep blue in colour.
(NH
4
)
2
SO
4
+Cu(OH)
2
+2NH
4
OH→[Cu(NH
3
)
4
]SO
4
+4H
2
O
(iii) The conclusion is Ca
2+
ion is present. The solution W is calcium chloride solution. With NaOH solution it gives white precipitates of Ca(OH)
2
which are insoluble in excess.
CaCl
2
+2NaOH→2NaCl+Ca(OH)
2
(iv) The conclusion is NH
4+
ion is present. The salt Z is ammonium chloride. With NaOH solution it libreates NH
3
gas which is alkaline in nature.
NH
4
Cl+NaOH
→
Δ
NaCl+H
2
O+NH
3