Question

After a reaction has gone to completion, it is not reversible:
True or false

Answer 1

In most cases, yes, a complete chemical reaction is irreversible.

However, there are reactions called equilibrium reactions that will fluctuate back and forth between products and reactants, basically "reversing" itself then "unreversing" itself until reaching equilibrium, but that's a really special case.

Answer 2

Chemical reactions are always reversible.