Final answer:
False. Concrete does not completely harden within 48 hours after it is poured. Full and complete hardening of concrete takes much longer as a result of the chemical reaction called hydration.
Step-by-step explanation:
False. Concrete does not completely harden within 48 hours after it is poured. While it may reach its initial set within this time frame, full and complete hardening of concrete takes much longer. The hardening process of concrete is a chemical reaction called hydration, in which the water in the concrete mixture reacts with the cement to form a solid structure. This reaction continues over an extended period of time, typically weeks or even months, depending on various factors such as the type of cement used and environmental conditions.