Fe⁺⁺ and Fe⁺⁺⁺ ( difference ? )
Answers
Answer:
The Correct Answer is mentioned below
Explanation:
The only difference between Fe2+ and Fe3+ is that Fe2+ is pale green and turns violet when exposed to water. When Fe3+ combines with thiocyanate ions, it turns blood red.
Fe2+ is a paramagnetic metal, whereas Fe3+ is a diamagnetic metal.
Add sodium hydroxide, NaOH, solution drop by drop to equal volumes of Fe2+ and Fe3+ ion solutions in separate test tubes until apparent colour changes and precipitation occurs. NaOH's hydroxide ions, OH-, readily combine with iron cations to form a variety of coloured precipitates.
Fe2+ + 2OH- = Fe(OH)2, which is a grass-green ppt. Fe(OH)3 is a reddish-brown ppt formed by Fe3+ + 3OH-.
The Iron(II)hydroxide, Fe(OH)2, steadily oxidises to Iron(III)hydroxide, Fe(OH)3, and the colour changes from grass green to reddish brown when the test tubes are left standing. Especially on the solution's surface. Fe2+ + e- = Fe3+ (oxidation).
The NaOH solution test, is widely used as a confirmatory test for the detection of Fe2+ & Fe3+ ions.