Electroliz potential question

[nhrock3]

what is the standard potential for the given x
?

 

[Borek]

Write Nernst equations for both half cells.

 

[nhrock3]

i can't interpret it
on the left
Pb gives 2 electrons
on the right H3O+ give H+
what is pt(s)
?

 

[Borek]

Solid (and inert) platinum electrode. Half cell is H⁺/H₂, Pt is only a contact.

 

[nhrock3]

so i have
Pb=Pb+2e
H_2+H^+=H_3O^+

what to do now
?

 

[Borek]

Read my answers again? I hate to repeat myself.

 

[nhrock3]

"Write Nernst equations for both half cells."

there are 4 ingredients for 4 given concentrations
i don't know how to build the expression for equlibrium.
and i don't know the total E0

ven if i would want to find the E0
i can't construct a total responce because the first give electrons and the other give H+

 

[Borek]

Write reaction equations for both half cells. These are separate reactions, and they are both producing or consuming electrons.

 

[nhrock3]

no

one consuumes electrons the other comsumes hirogen

 

[Borek]

Try to write reactants and products for both.

 

[nhrock3]

i have
Pb=Pb+2e
H_2+H^+=H_3O^+

what to do now
?

 

[Borek]

The second one is wrong. Hydrogen is oxidized to H⁺ in presence of water.

 

[nhrock3]

i don't know how to intepret it

 

[Borek]

Let's try with something simpler - hydrogen oxidized to H⁺.

 

[nhrock3]

H=H^+ +e

 

[Borek]

Apart from the fact that hydrogen is not H, that's correct - as you see, electrons are involved after all. What happens to H⁺ in water?

 

[nhrock3]

dont know

 

[Borek]

What is H₃O⁺?

--
methods

 

[nhrock3]

ok so it transfrmed into H3o+

 

[nhrock3]

but i can't solve this question