In an endothermic reaction, a greater extent of reaction would correspond to a higher outlet temperature.
true or false?

False

Explanation:

In an endothermic reaction, it consume the energy at greater extent and a reaction provide the lower temperature if, the system is in the adiabatic state.

An endothermic is the process in which it absorb the energy in the formation of heat from the surrounding.

Endothermic reaction is the process in which the net result decreases the temperature because the endothermic reaction absorb heat and then store the heat energy in the form of bond in the reaction.  

And this reaction occur when the energy break the energy bonds in the reactant. Therefore, all the endothermic reaction occur in the form of energy so that is why the temperature decreases.