What does the backward arrow ( ← ) mean in a chemical equation?

the reaction arrow is used most frequently and indicates a reaction occurring from the reactants to the products. The arrow's head points in the direction the reaction proceeds in.

odds are decent that your handwriting right now looks a little bit different than it did five years ago, and will look different again in five more. when i look back through my notebooks from middle school to now, i see a long, slow progression from meticulous and teeny letters to bigger, sloppier ones, plus a few side detours: sometime in high school, for example, i decided those loopy cursive lowercase f’s were just the coolest, adopting them as the lone rep for cursive in my otherwise all-print handwriting.

explanation:

lithosphere and asthenosphere