For a cell reaction to be sponteanous, the standard cell potential must be positive.
<h3>What is a sponteanous cell reaction?</h3>
We define a cell reaction as sponteanous when the value of the standard cell potential is positive. If the standard cell potential is negative then the reaction is not sponteanous.
The question here is incompete but we know that the reactions that are sponteanous will all have a positive standard cell potential.