Campden vs. Potassium Sorbate

How does Campden differ from Potassium Sorbate?

Campden from reading should be used before to kill wild yeasts and Potassium Sorbate to prevent further fermentation. Wouldn’t that just be also killing off the yeast?

Maybe Campden dissipates and Potassium Sorbate does not?

The amount of K-meta that you are adding is not enough to kill of the amount of yeast that you have after fermentation. You will need to use potassium sorbate as well if you are planning on backsweetening. If you are planning on stabilizing to backsweeten, make sure to use K-meta in conjunction with the potassium sorbate.