All Questions
Tagged with aqueous-solution redox
68
questions
3
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1
answer
4k
views
Why does green ferrous sulfate solution change color to yellow upon addition of hydrochloric acid?
I was demonstrating the formation of $\ce{Fe(OH)2}$ precipitate at school when the light green $\ce{FeSO4}$ I was using reacted with dil. $\ce{HCl}$ turned yellow. This only happened with dil. $\ce{...
- 143
0
votes
1
answer
390
views
Balancing complex redox reaction of gold treated with sodium cyanide
How would you balance this reaction:
$$\ce{Au(s) + NaCN(aq) + O2(g) + H2O(l)-> Na[Au(CN)2](aq) + NaOH(aq)}?$$
Here’s what I’m came up with. First we can balance any atoms besides hydrogen and ...
- 145
-1
votes
1
answer
306
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Aluminum powder from aluminum sulfate?
I recently did the experiment where you drop a piece of iron in an aqueous solution of copper sulfate. After a while, the piece of iron gets coated with a fluffy coating of copper that can be dried ...
- 113
3
votes
0
answers
1k
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Number of moles of acidified potassium dichromate required to liberate 6 moles of iodine from an aqueous solution of iodate ions
I came across this question in a recent exam I had taken:
How many moles of acidified $\ce{K2Cr2O7}$ is required to liberate 6 moles of $\ce{I2}$ from an aqueous solution of $\ce{I-}$ ?
So this is ...
- 426
2
votes
0
answers
408
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Effect of charge density on electrolysis of dilute sulphuric acid
I am told that if electrolysis of dilute sulfuric acid is performed under high charge density, then the following reaction takes place at anode instead of evolving oxygen:
$$\ce{2 HSO4- -> H2S2O8 +...
- 363
1
vote
2
answers
168
views
Indicators of Cu(I) or Cu(II)
We performed an experiment in class where we placed a piece of copper wire in a solution of silver nitrate, we were tasked with predicted the mass of copper that should react and the mass of silver ...
1
vote
0
answers
55
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Can Methylene Blue Detect Spoilage in Food?
Initially, there is already a product which is a sensor based on Methylene Blue, which can detect changes in oxygen levels in a packaging. However, as our thesis project, we decided to take on this ...
- 11
1
vote
2
answers
1k
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How can iodine oxidise hydrogen peroxide?
The following is mentioned in NCERT (government textbook in India used in all schools) under chemical properties of $\ce{H2O2}:$
(iv) Reducing action in basic medium
$$\ce{I2 + H2O2 + 2 OH- -> 2 I-...
- 1,693
1
vote
0
answers
40
views
Stability of cuprous iodide in aqueous solution
An aqueous solution of $\ce{Cu+}$ is usually unstable, but $\ce{CuI}$ is stable. Explain. $E^\circ(\ce{Cu^2+/Cu+}) = \pu{0.153 V}$ and $E^\circ(\ce{Cu+/Cu}) = \pu{0.521 V}.$
I found this question ...
- 131
0
votes
1
answer
165
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How to know which reduction and oxidation reactions occurred?
We just had a lab experiment on galvanic cells and we used 0.5 M and 1 M iron(III) nitrate solution at the anode (iron electrode) and 1 M and 0.5 M copper(II) nitrate solution at the cathode (copper ...
0
votes
2
answers
208
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Why do we use [H⁺] and [OH⁻] in balancing redox reactions instead of using [H₃O⁺] and [OH⁻]? [duplicate]
For what reason is it universally agreed upon that we use $$\ce{H+ + OH-}$$ ions in balancing water on either side of the reaction, but not the $$\ce{H3O+}$$ ions?
- 13
4
votes
1
answer
4k
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Reaction of aqueous sodium carbonate with aluminum foil
Aqueous sodium hydroxide is known to react with aluminum foil in an exothermic, hydrogen-gas releasing reaction like $$\ce{2NaOH(aq) + 2Al(s) + 2H2O(\ell) → 2NaAlO2(aq) + 3H2(g)}$$
However, on ...
- 1,556
0
votes
1
answer
234
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Balancing the chemical equation using Oxidation Number Method [closed]
Permanganate ion reacts with bromide ion in basic medium to give manganese dioxide and bromate ion. Write the balanced ionic equation for the reaction.
Please balance the equation using the oxidation ...
- 11
-1
votes
2
answers
57
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Is this balanced redox equation correct? [closed]
I'm trying to balance an equation using oxidation numbers
$\ce{MnO4^- + H+ + Cl- -> Mn^2+ + Cl2 + H2O}$
my suggestion:
$\ce{MnO4- + 8H+ + 5Cl- → Mn^2+ + 2.5Cl2 + 4H2O}$
the 2.5 $\ce{Cl2}$ is ...
- 11
0
votes
1
answer
161
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Redox titration or iron(II)
The concentration of $\ce{Fe^2+(aq)}$ can be determined by a redox titration using
A. $\ce{KBr}$
B. $\ce{SnCl2}$
C. $\ce{KMnO4}$ (basic)
D. $\ce{KBrO3}$ (acidic)
Can anyone please help me on this ...
- 11