Exam preparation MCQs with answers

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An open system is one in which____________________?
  • (A)  mass does not cross boundaries of the system, though energy may do so
  • (B)  neither mass nor energy crosses the boundaries of the system
  • (C)  both energy and mass cross the boundaries of the system
  • (D)  mass crosses the boundary but not the energy
  • (E)  thermodynamic reactions do not occur
A closed system is one in which_________________________?
  • (A)  mass does not cross boundaries of the system, though energy may do so
  • (B)  mass crosses the boundary but not the energy
  • (C)  neither mass nor energy crosses the boundaries of the system
  • (D)  both energy and mass cross the boundaries of the system
  • (E)  thermodynamic reactions take place