Ferrous hydroxide.

[Primarygun]

Here I want to ask you a couple of questions.Thanks

1. What happens when ferrous hydroxide is heated strongly?

My idea is that it would turn to ferrous oxide at once and later oxidizes by oxygen in air.

And what's the colour of unhydrous ferrous oxide and hydroxide?

2.Does hypochlorite react with acidified potassium permanganate?

Thanks for attention

[h4tt3n]

If Ferrous hydroxides are heated above just a few hundred deg. C, water is split away as vapor. For instance:

 

Ferrihydrite => hematite + water

 

5 Fe2O3.9 H2O(s) => 5 Fe2O3(s) + 9 H2O(g)

 

Note that the ferrous oxide is neither oxidized nor reduced with heat alone!

 

 

Regarding color...

 

-Some of the oxides:

 

Hematite Fe2O3 has a beautiful brownish red color.

 

Magnetite Fe3O4 is blackish grey

 

Wustite FeO is greyish blue

 

-And The hydroxides:

 

Goethite alpha-FeOOH is bright yellowish brown

 

Lepidocrocite gamma-FeOOH is orange

 

Ferrihydrite is reddish brown

 

Best regards

Michael

[Primarygun]

Thanks. I'm afraid I gave the wrong detail to you.

1. What happens when ferrous hydroxide is heated strongly?

It should be ferriic hydroxide.

It's my fault, sorry may you figure it out once more?

[RyanJ]

Thanks. I'm afraid I gave the wrong detail to you.

1. What happens when ferrous hydroxide is heated strongly?

It should be ferriic hydroxide.

It's my fault' date=' sorry may you figure it out once more?[/quote']

 

Umm, there is no such compound, do you mean ferric hydroxide (AKA iron(III) hydroxide)? [ce]Fe(OH)3[/ce]

 

If you do then it decomposes at about 500°C...

 

Cheers,

 

Ryan Jones

[YT2095]

I think he realised that

 

btw, Nice answer H4tt3n!

[woelen]

Ferrous hydroxide certainly exists. It is an almost white solid. It is very easily oxidized though and then it durns olive-green. On even further oxidation it finally becomes rust/brown. At that stage it is converted to an iron (III) compound completely.

[Primarygun]

ferriic hydroxide.

Sorry, it is Iron(II) hydroxide.

A question set in my examination asks about

Will iron(II) hydroxide turn black upon strong heating?

[RyanJ]

Sorry' date=' it is Iron(II) hydroxide.

A question set in my examination asks about

Will iron(II) hydroxide turn black upon strong heating?[/quote']

 

I would presume so... I can find very little information about iron(II) hydroxide... even the CRC book lack melting and boilling point information.

 

Cheers,

 

Ryan Jones

[YT2095]

all I have in mine is Fe(OH)2 and Fe(OH)3 decompose on heating, again, no temp given either.

 

Fe2O3 is a red/brown and Fe3O4 is Black/red (and magnetic)

but FeO is plain Black.

[woelen]

Sorry' date=' it is Iron(II) hydroxide.

A question set in my examination asks about

Will iron(II) hydroxide turn black upon strong heating?[/quote']

Yes, it will, but it must be heated in an environment, absolutely free of oxygen, otherwise the iron in it is oxidized to the +3 oxidation state. I do not know, however, how much it must be heated.