Talk:Chromate and dichromate

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Untitled[edit]

Dichromate isn't a salt, it's an ion.

See the salt article. Anions are often named with respect to their conjugate acids, so e.g., dichromate is the salt of chromic acid, and nitrate is the salt of nitric acid. --Diberri | Talk 03:27, Sep 15, 2004 (UTC)

If sodium chromate is so common why is there no pecific page about it?

Question about H3O+[edit]

2 CrO42− + 2 H3O+ → Cr2O72− + 3 H2O

Note: Someone please check above for accuracy, H3O+, should it not be H2O if it's in an aqueous solution, if this is not true, please send me a reason why, to psychicpanda@gmail.com, thanks, otherwise fix the error. Or is this because to be balanced on one side it requires 2 H3O+ to balance the 2-, though I thought that in water, it does not need to be balanced, unless as stated above its in equilibrium, which means that it doesn't need to be ionically balanced, but balanced on both sides, as in the anions and cations are equal on both sides, but not adding up to a neutral charge.

The reaction is correct. H3O+ can exist in solution; it's a hydrated H+ ion, which you could get by dissolving an acid. See: Acid#Chemical characteristics. Hashproduct 01:30, 2 May 2007 (UTC)[reply]
Also, technically, both H30+ and HO- exist in all water, at concentrations varying inversely and directly with pH, respectively. Though their concentration in neutral water is pretty low. Calvacadeofcats (talk) 01:37, 12 December 2008 (UTC)[reply]
You cannot be serious. How would this equation be correct? First of all, there is zero net charge on the left side and there is -2 on the right side; second, the number of hydrogen atoms is 6 on the left side and 4 on the right side. Thus this barely qualifies as an "equation". 91.120.152.221 (talk) 21:32, 2 June 2009 (UTC)[reply]
Uhm. The equation is correct. On the LHS, the charge is 2*(-2) + 2*(+1) = -4 + 2 = -2, and on the RHS, the charge is -2. The number of hydrogen atoms on LHS is 2*3 = 6, and the number of hydrogen atoms on RHS is 3*2 = 6. Where's the error?—Tetracube (talk) 21:44, 2 June 2009 (UTC)[reply]
I have checked the reaction equation; it is correct. The charge is balanced with a net -2 charge on both sides. The number of Cr atoms with 2 on both sides, the number of O atoms with 10 on both sides, and the number of H atoms with 6 on both sides, are all correctly balanced. H Padleckas (talk) 00:45, 22 October 2009 (UTC)[reply]

Separate and improve?[edit]

I suggest separating chromate and dichromate into two articles. They also both need a polish and more information. Bob782 (talk) 13:50, 6 February 2008 (UTC)[reply]

I have decided to move this article to Chromate and dichromate, because this is the main article covering both. Because of their interconversion, these two species are linked together. H Padleckas (talk) 00:49, 22 October 2009 (UTC)[reply]

Predominance Diagram[edit]

"The red line on the predominance diagram is not quite horizontal due to the simultaneous equilibrium with the chromate ion."

Shouldn't that be vertical? Vmelkon (talk) 15:05, 5 May 2011 (UTC)[reply]

Issue about the opening[edit]

At the top of the page, it states that: "This article is about chromium(VI) cation. For chromium(III) cation, see chromite (compound)." but surely it is an anion, not a cation.--Pianoplonkers (talkcontribs) 10:49, 26 May 2011 (UTC)[reply]