A certain half-reaction has a standard reduction potential E⁰red = +0.63V. An engineer proposes using this half-reaction at the cathode of a galvanic cell that must provide at least 1.30V of electrical power. The cell will operate under standard conditions.
(a) Is there a minimum standard reduction potential that the half-reaction used at the cathode of this cell can have? If so, write "yes" and calculate the minimum. Round your answer to 2 decimal places. If there is no lower limit, write "no".
(b) Is there a maximum standard reduction potential that the half-reaction used at the cathode of this cell can have? If so, write "yes" and calculate the minimum. Round your answer to 2 decimal places. If there is no upper limit, write "no".

a) YES, this is a minimum standard reduction potential and

b) NO maximum reduction potential of half cell of cathode.

Explanation:

Given that the galvanic cell must provide at least 1.30 V  of electrical power . that denotes that

Here, the standard reduction potential of the half-cell reaction of anode is + 0.63 V

i.e

We know that:

If ; then > 1.30 V

Also; If  ; then 1.30 V

This is because the  cell supply minimum electrical power that is 1.30 V , Hence reduction potential of half- cell reaction at cathode will be minimum at 1.93 V

Therefore, from the foregoing, we conclude that: YES, this is a minimum standard reduction potential.

So, if reduction potential value of the half-cell reaction used at cathode is greater than 1.93 (V); we get at least 1.30 V or greater than 1.30 V cell emf.

As such, No maximum reduction potential of half cell of cathode.

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the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.