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### Topic: Law of equivalents  (Read 1921 times)

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##### Law of equivalents
« on: October 10, 2013, 01:12:53 PM »
I got very confused by studying this. I could really use some good explanation. For example, the equivalent unit of K2Cr2O7 is 1/6K2Cr2O7. If in a solution nK2Cr2O7=0.1mol, we should have 6 times more of 1/6K2Cr2O7 because 6*1/6=1, but it's not true. Please help .

#### magician4

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##### Re: Law of equivalents
« Reply #1 on: October 10, 2013, 02:46:17 PM »
labelling "equivalent" without specifying what something should be equivalent to is meaningless

your example would be relevant in redox reactions with K2Cr2O7 , where each chromium went from + VI to + III , and the substance oxidized would supply one electron each: here the molar ratios, i.e. "the equivalent"  would be 1:6
... but you have to specify this

regards

Ingo
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##### Re: Law of equivalents
« Reply #2 on: October 11, 2013, 07:24:28 AM »
That's not the point of my confusion. I have meant for the situation you wrote.
Now, can you explain the thing I asked at the beginning?

#### Borek

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##### Re: Law of equivalents
« Reply #3 on: October 11, 2013, 08:11:34 AM »
I got very confused by studying this. I could really use some good explanation. For example, the equivalent unit of K2Cr2O7 is 1/6K2Cr2O7. If in a solution nK2Cr2O7=0.1mol, we should have 6 times more of 1/6K2Cr2O7 because 6*1/6=1, but it's not true. Please help .

Unless I am missing something, you got it reversed. If it is 1/6, then to get 1 equivalent you need 1/6 of the mole, not 6 moles.
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