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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Fish200398 on February 21, 2020, 02:27:34 PM

Title: when k2cro4 become k2cr2o7 does k2cro4 undergo oxidation?
Post by: Fish200398 on February 21, 2020, 02:27:34 PM

 in this reaction 2k2cro4 + h2so4 --> k2cr2o7 + k2so4 + h2o

when k2cro4 become k2cr2o7 does k2cro4 undergo exidation?

Title: Re: when k2cro4 become k2cr2o7 does k2cro4 undergo oxidation?
Post by: chenbeier on February 21, 2020, 02:36:24 PM

No, determine the oxidation numbers of chromium.

Title: Re: when k2cro4 become k2cr2o7 does k2cro4 undergo oxidation?
Post by: Fish200398 on February 21, 2020, 02:44:34 PM

the compound gets oxygen but in this case not oxidation? how can there is extra O attached to Cr without Cr being oxidized?

Title: Re: when k2cro4 become k2cr2o7 does k2cro4 undergo oxidation?
Post by: OuJej1 on February 24, 2020, 03:37:43 AM

That's not just simple oxidation - try thinking about the bonds of EACH Chromium in K₂Cr₂O₇.

Title: Re: when k2cro4 become k2cr2o7 does k2cro4 undergo oxidation?
Post by: Borek on February 24, 2020, 07:00:22 AM

As it was already said - this is not an oxidation at all.

You might want to refresh what oxidation is. Hint: no, it is not about number of bonds to oxygen. While number of such bonds often changes during oxidation, that's only a secondary effect which sometimes can be misleading. There is another, underlying change that is important.

Title: Re: when k2cro4 become k2cr2o7 does k2cro4 undergo oxidation?
Post by: Fish200398 on February 25, 2020, 02:46:39 PM

Oh, yes, you guys were right.. thats what oxidizing means