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Topic: Equivalent based questions (Valency Factors)  (Read 249 times)

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Offline Win,odd Dhamnekar

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Equivalent based questions (Valency Factors)
« on: September 13, 2021, 11:11:00 AM »
Answers to d : 5 moles of Ferrous Oxalate (FeC2O4) are required to reduce 2 moles of Potassium Permanganate in acidic medium

Answer to e: Redox equation is [tex]K_2Cr_2O_7 + 3 Cu_2S + 14 H^+ \rightarrow 6 Cu^{2+} +3 S + 7 H_2O + 2K^+ + 2 Cr[/tex]

From the aforesaid equation, we can say that [itex]\frac56[/itex] moles of  K2Cr2O7 is required to react completely with 2.5 moles of  Cu2S in acidic medium.
« Last Edit: September 13, 2021, 12:20:04 PM by Win,odd Dhamnekar »
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Offline Borek

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Re: Equivalent based questions (Valency Factors)
« Reply #1 on: September 13, 2021, 12:42:43 PM »
When using dichromate for oxidation Cr is not reduced to solid metal.
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Offline Win,odd Dhamnekar

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Re: Equivalent based questions (Valency Factors)
« Reply #2 on: September 13, 2021, 01:45:04 PM »
My answer to a) is wrong. I have two probable  answers 1)75 ml of K2Cr2O7.

It is computed as under:
0.3 M = 300 mmol  :rarrow:50 ml of 300mmol = 15mmol
 So  volume of Potassium Dichromate × 0.2 M = 15mmol :rarrow: volume of K2Cr2O7= 75 ml

2) Using this formula v.f.1 × M1 × volume1= v.f.2× M2 × volume2
Plugging in the values available with us into this formula, we have 6×0.2M× V1=2×0.3M × 50 ml

= 25 ml of Potassium Dichromate

Which of the above answer is correct?

« Last Edit: September 13, 2021, 02:03:14 PM by Win,odd Dhamnekar »
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5) Think 6) Understand 7) Inference 8) take decision [Believe or disbelieve, useful or useless, healthy or unhealthy, cause or effect, favorable or unfavorable, practical or theoretical, practically possible or practically impossible, true or false or  any other required criteria]

Offline Borek

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Re: Equivalent based questions (Valency Factors)
« Reply #3 on: September 13, 2021, 04:19:11 PM »
Ignoring hints won't help you.
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