Question 1 of 5
Define the **Zeroth law** and **First law** of thermodynamics.
Why: This is the exact definition from the 2017 question bank. The answer provides complete definitions with mathematical expressions, examples, and meets the 50-80 word minimum per law for short answer questions.
Question 2 of 5
Which of the following correctly states the **Zeroth law of thermodynamics**?
A. Energy cannot be created or destroyed.
B. If two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with each other.
C. Entropy of an isolated system always increases.
D. At absolute zero, entropy approaches a minimum value.
A
Energy cannot be created or destroyed.
B
If two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with each other.
C
Entropy of an isolated system always increases.
D
At absolute zero, entropy approaches a minimum value.
Why: The Zeroth law defines thermal equilibrium transitivity: if system A is in equilibrium with C, and B is in equilibrium with C, then A and B are in equilibrium with each other. This establishes temperature as a state function. Option B matches this definition exactly. Option A is First law, C is Second law, D is Third law.[4][6][7]
Question 3 of 5
State the **three statements of the Second law of thermodynamics** and the **Third law of thermodynamics**.
Why: The Second law is commonly stated in Clausius and Kelvin-Planck forms, introducing irreversibility and entropy increase. Third law defines entropy at absolute zero. Answer includes statements, math, and examples meeting word requirements.[1][6][8]
Question 4 of 5
Match the following laws of thermodynamics with their correct descriptions:
1. Zeroth Law a. Entropy approaches minimum at 0 K
2. First Law b. Basis of temperature measurement
3. Second Law c. Conservation of energy
4. Third Law d. Entropy of universe increases
A
Zeroth Law - Basis of temperature measurement
B
First Law - Conservation of energy
C
Second Law - Entropy of universe increases
D
Third Law - Entropy approaches minimum at 0 K
Why: Zeroth law defines thermal equilibrium for temperature (b). First law is \( \Delta U = Q - W \) (c). Second law states entropy increase in isolated systems (d). Third law: \( S = 0 \) at 0 K for perfect crystals (a). This matching is standard across sources.[7][8]
Question 5 of 5
The expression \( \oint \delta W \leq 0 \) is an outcome of which Law of Thermodynamics?
A
Zeroth
B
First
C
Second
D
Third
Why: The expression \( \oint \delta W \leq 0 \) relates to the second law of thermodynamics, which introduces the concept of entropy and directionality of processes. The Clausius inequality \( \oint \frac{\delta Q}{T} \leq 0 \) is a direct statement of the second law for cyclic processes, and the work form follows from the first law combined with it. For reversible processes, equality holds, but irreversibility leads to inequality. Thus, option C is correct.
