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A current of 10.4 a is applied to 1.25 l of a solution of 0.552 m hbr converting some of the h + to h2(g), which bubbles out of solution.

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The question is incomplete:
Complete question is read as:
A current of 10.4 a is applied to 1.25 l of a solution of 0.552 m hbr converting some of the h + to h2(g), which bubbles out of solution.What is the pH of the solution after 69 minutes?
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Solution:
Initial number of moles of H+ ions = molarity of solution X volume of solution
                                                       = 0.552 X 1.25
                                                        = 0.69

Now, during electrochemical reaction conc. of H+ ions will decrease in solution.

Using Faraday's law, we know that,
number of moles of H(+) discharged at the electrode  = n = Q/(z•F) 
where, Q = total electric charge in Coulomb
F = Faraday constant = 96485 C mol−1 
z =  electrons transferred per ion = 1 (in present case)

We also know that, Q = I x t  = 10.4 X 69 X 60 = 43056 C

∴ n = Q/(z•F)
      = (43056)/(1 X 96500) = 0.4462

Now, number of moles of H+ ions left in solution = 0.69 - 0.4462 = 0.2438

Now, Molarity of solution = number of moles/volume of solution
                                            = 0.2438 / 1.25 
                                            = 0.195 M
Finally, conc. of [H+] = 0.195 M
∴ pH = -log [H+] = -log[0.195] = 0.71


jayilych4real

The pH of the solution after 69 minutes is 0.71.

Calculations and Parameters:

Given that the initial number of moles of H+ ions = molarity of solution X volume of solution

= 0.552 X 1.25

= 0.69

Then, during the electrochemical reaction, conc. of H+ ions will decrease in solution.

If we use Faraday's law, we know that,

  • number of moles of H(+) discharged at the electrode  = n = Q/(z•F)
  • where, Q = total electric charge in Coulomb
  • F = Faraday constant = 96485 C mol−1
  • z =  electrons transferred per ion = 1 (in present case)

It is also known that,

Q = I x t  

= 10.4 X 69 X 60

= 43056 C

Therefore,

n = Q/(z•F)

= (43056)/(1 X 96500)

= 0.4462

Hence, the number of moles of H+ ions left in solution

= 0.69 - 0.4462

= 0.2438

Then, the molarity of solution = number of moles/volume of solution

= 0.2438 / 1.25

= 0.195 M

Finally, conc. of [H+] = 0.195 M

Therefore,

pH = -log [H+]

= -log[0.195]

= 0.71

Read more about pH levels here:

https://brainly.com/question/1810086

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