What role does the salt bridge play in a voltaic cell?

it allows electrons to flow from the anode to the cathode.

it allows migration of ions from one half–cell to the other.

it contains the electrodes.

it creates the oxidation reaction.

Option (b) is the correct answer.

Explanation:

A salt bridge is a device which helps in maintaining electrical neutrality between the solution at both ends of cathode and anode.

Basically, a salt bridge helps in migration of ions in oxidation-reduction half reactions occurring at anode and cathode.

Thus, we can conclude that role of a salt bridge in a voltaic cell is that it allows migration of ions from one half–cell to the other.

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).

aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.