Answer:
The time recorded in the lab notebook is shorter than the true reaction time because the reaction starts the moment the two solutions were mixed
Step-by-step explanation:
A chemical reaction is "a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction" (Oxford dictionary).
A chemical reaction begins immediately the reactants are mixed together in a reaction vessel because the particles of the reactants immediately begin to collide with each other. There is no lost time before reactions begins!
This implies that, the time recorded in the lab notebook is shorter than the true reaction time because the reaction starts the moment the two solutions were mixed.