When an isolated thermodynamic system executes a process,

ANS:D - no chemical reaction takes place within the system.

The correct statement is: no chemical reaction takes place within the system. Explanation: In an isolated thermodynamic system, which is defined as a system that does not exchange heat, work, or matter with its surroundings, the total energy within the system remains constant. While work can indeed be done and heat transfer can occur within the system during a process, there are no interactions with the surroundings, so no mass flow occurs across the boundary of the system. Additionally, in an isolated system, no chemical reactions take place within the system, as there are no external influences or interactions. Therefore, the statement about no chemical reaction occurring within the system is accurate for an isolated thermodynamic system.