Question

The standard emf for the cell using the overall cell reaction below is +2.20 V: 2Al(s) + 3I2 (s) → 2Al3+ (aq) + 6I− (aq) The emf generated by the cell when [Al3+] = 5.0 ⋅ 10−3 M and [I−] = 0.10 M is ________ V. The standard emf for the cell using the overall cell reaction below is +2.20 V: (s) + (s) (aq) + (aq) The emf generated by the cell when [] = 5.0 M and [] = 0.10 M is ________ V. 2.20 2.41 2.10 2.30 2.23

Answer 1

Answer: +2.10V

Step-by-step explanation:

`2Al(s)+3I_2(s)\rightarrow 2Al^(3+)(aq)+6I^-(aq)`

Using Nernst equation :

`E_(cell)=E^o_(cell)-(0.059)/(n)\log K`

`E_(cell)=E^o_(cell)-(0.059)/(n)\log [Al^(3+)]^2* [I^-]^6`

where,

`E^o_(cell)` = standard emf for the cell = +2.20 V

n = number of electrons in oxidation-reduction reaction = 6

`E_(cell)` = emf of the cell = ?

`[Al^(3+)]` = concentration =
`5.0* 10^(-3)M`

`[I}^(-)]` = concentration =
`0.10M`

Now put all the given values in the above equation, we get:

`E_(cell)=+2.20-(0.059)/(6)\log [5.0* 10^(-3)]^2* [0.10]^6`

`E_(cell)=2.10V`

The standard emf for the cell using the overall cell reaction below is +2.10 V