Frequently Asked Questions
True/False questions present statements about thermodynamic concepts such as heat, work, internal energy, and enthalpy. Students must determine whether each statement is correct based on scientific principles.
They help students quickly test conceptual clarity. Since thermodynamics involves definitions, laws, and sign conventions, True/False questions expose misunderstandings efficiently.
Common topics include system and surroundings, types of thermodynamic systems, internal energy, heat and work, enthalpy, the first law of thermodynamics, Hess’s law, and state versus path functions.
Yes. Even when the exam format uses MCQs or numerical questions, many problems are conceptually similar to True/False statements that test deep understanding.
The law states that energy is conserved and can be written as \( \Delta U = q + w \), meaning the change in internal energy equals heat supplied plus work done on the system.
Heat is energy transferred due to temperature difference, while work is energy transfer caused by mechanical processes such as expansion or compression.
Sign conventions determine whether energy enters or leaves the system. Misunderstanding signs like positive heat or negative work can lead to incorrect answers in numerical problems.
A thermodynamic system is the portion of the universe chosen for study, separated from its surroundings by a real or imaginary boundary.
An open system exchanges both matter and energy, a closed system exchanges only energy, and an isolated system exchanges neither matter nor energy.
State functions depend only on the initial and final states of a system, not on the path taken. Examples include internal energy \(U\), enthalpy \(H\), pressure, and temperature.
Their values depend on the specific process or path followed during the transformation, not just the initial and final states.
Enthalpy is a thermodynamic quantity defined as \( H = U + PV \) and is useful for measuring heat changes at constant pressure.
The enthalpy change \( \Delta H \) indicates whether a reaction releases heat (exothermic) or absorbs heat (endothermic).
Hess’s law states that the total enthalpy change of a reaction is independent of the pathway, allowing calculation of enthalpy changes through multiple reaction steps.
A reversible process occurs through infinitesimally small equilibrium steps, while an irreversible process occurs rapidly and cannot be reversed without changing the surroundings.