A system in which state variables have constant values throughout the system is called in a state of

Options

A. Equilibrium
B. Non-equilibrium
C. Transition
D. Zero entropy

Answer

To solve the question, we need to understand the concept of state variables in thermodynamics and how they relate to the state of a system.

### Step-by-Step Solution:

1. **Identify State Variables**:
- State variables are properties that define the state of a system. Common state variables include temperature, pressure, volume, number of moles, and concentration.

2. **Understand the Concept of Constant Values**:
- The question states that the state variables have constant values throughout the system. This means that there is no change in these properties over time.

3. **Consider the Implications of Constant State Variables**:
- When state variables are constant, it implies that the system is not undergoing any change. In a chemical context, this often means that the reactants and products are in a stable state.

4. **Relate to Chemical Equilibrium**:
- In a chemical reaction, when the rates of the forward and reverse reactions are equal, the concentrations of reactants and products remain constant. This is known as chemical equilibrium.

5. **Conclude the State of the System**:
- Since the state variables (like concentration) are constant, the system is in a state of equilibrium.

### Final Answer:
A system in which state variables have constant values throughout the system is called in a state of **equilibrium**.

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