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Qualitative Analysis: Cations
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Confirmatory tests and coloured precipitates
JEE Main level
Single correct option
Difficulty 2 of 3
qc141
Rinmann's green, obtained when a zinc salt is moistened with
Co
(
NO
X
3
)
X
2
and ignited, is
A
CoZnO
X
2
(cobalt zincate,
CoO
⋅
ZnO
)
B
Co
X
3
O
X
4
C
CoCO
X
3
D
Zn
(
NO
X
3
)
X
2
⋅
CoO
Answer: A
Ignition of
ZnO
with cobalt(II) oxide gives the green mixed oxide
CoZnO
X
2
(Rinmann's green).
Co
X
3
O
X
4
is black and
CoCO
X
3
is pink.
Practice Qualitative Analysis: Cations
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