Question

Use the standard reduction potentials located in the 'Tables' linked above to calculate the equilibrium constant for the reaction:

Ni2+(aq) + Cu(s) ---> Ni(s) + Cu2+(aq)
Hint: Carry at least 5 significant figures during intermediate calculations to avoid round off error when taking the antilogarithm.
Equilibrium constant: __________ delta G° for this reaction would be _________ ( greater /less ) than zero.
What is the calculated value of the cell potential at 298K for an electrochemical cell with the following reaction, when the Cu2+ concentration is 4.38×10-4 M and the Al3+concentration is 1.08 M ?
3Cu2+(aq) + 2Al(s)----> 3Cu(s) + 2Al3+(aq)

Answer 1

Check the explanation

Step-by-step explanation:

cell CuE Ecell 0.337 (-0.14) Ecl0.477 V

Since
`E^o_( cell ) > 0` , the value of \Delta G^o will be negative.

`\Delta G^o < 0`

`\Delta G^o =-nFE^o_( cell ).`.....(1)

But

`\Delta G^o =-RT ln K`......(2)

From (1) and (2)

`\Delta G^o =-RT ln K=-nFE^o_( cell )`

ln K =
`(nFE^o_( cell ) )/(RT )`

ln K =
`( 2 * 96500 * 0.477 )/(8.314 * \left ( 25+273.15 \right ) )`

ln K =37.139

K =
`1.3468 * 10^(16)`

Hence, the value of the equilibrium constant is
`1.35 * 10^(16)`