Entropy Calculator

Formula

The formula to calculate the change in Entropy (E) is:

\[ E = n \cdot R \cdot \ln\left(\frac{v2}{v1}\right) \]

Where:

\(E\) is the change in entropy (J/K)
\(n\) is the number of moles
\(R\) is the gas constant (8.3145 J/mol*K)
\(v1\) is the initial volume (m³)
\(v2\) is the final volume (m³)

Entropy Definition

Entropy is defined as the resistance of a substance to convert thermal energy into mechanical work. It is a measure of the disorder or randomness in a system. In thermodynamics, entropy is a central concept that helps explain the direction of spontaneous processes and the efficiency of energy transformations.

Example Calculation

Let's assume the following values:

Number of Moles (n) = 2 moles
Initial Volume (v1) = 1 m³
Final Volume (v2) = 3 m³

Using the formula:

\[ E = 2 \cdot 8.3145 \cdot \ln\left(\frac{3}{1}\right) \approx 18.27 \text{ J/K} \]

The Change in Entropy (E) is approximately 18.27J/K.