Qualitative Analysis Flashcards
Colour of [Fe(H2O)6]2+
Colour + NaOH
Is it soluble in XS NaOH?
Pale green
Green
Insoluble in XS NaOH
Colour of [Fe(H2O)6]3+
Colour + NaOH
Is it soluble in XS NaOH?
Pale yellow
Orange-brown
Insoluble in XS NaOH
Colour of [Cu(H2O)6]2+
Colour + NaOH
Is it soluble in XS NaOH?
Pale Blue
Blue
Insoluble in XS NaOH
Colour of [Mn(H2O)6]2+
Colour + NaOH
Is it soluble in XS NaOH?
Pale pink
Brown
Insoluble in XS NaOH
Colour of [Cr(H2O)6]3+
Colour + NaOH
Is it soluble in XS NaOH?
Violet
Green
It is soluble in XS NaOH. The solid Cr(OH)3 reacts with NaOH to form a dark green solution of [Cr(OH)6]3-
How would you test for the ammonium ion?
React with NaOH. If ammonia is produced then the damp red pH indicator paper should go blue
How would you test for the carbonate ion?
Add dilute HNO3. You would see effervescence as CO2 is produced
How would you test for the sulphate ion?
Add Ba2+ ions (usually through barium nitrate) and look for a white precipitate of BaSO4
How would you test for the halide ions?
Add AgNO3 and look for a precipitate
What colour is the silver Chloride precipitate?
White
What colour is the silver bromide precipitate?
Cream
What colour is the silver Iodide precipitate?
Yellow
Is AgBr soluble in dilute NH3?
No only AgCl is
Is AgI soluble in conc NH3?
Yes and so is AgBr
What is the order of the anion tests? And why
Carbonate - sulfate/halide don’t produce CO2 (no carbon)
Sulfate - BaCO3 is also a white precipitate
Halide - both Ag2CO3 and Ag2SO4 are precipitates