What is the change in entropy when 1 mole of an ideal gas expands isothermally f
Practice Questions
Q1
What is the change in entropy when 1 mole of an ideal gas expands isothermally from 10 L to 20 L at 300 K?
0.5 J/K
1.0 J/K
1.5 J/K
2.0 J/K
Questions & Step-by-Step Solutions
What is the change in entropy when 1 mole of an ideal gas expands isothermally from 10 L to 20 L at 300 K?
Step 1: Identify the variables needed for the calculation. We have 1 mole of gas (n = 1), the gas constant (R = 8.314 J/(mol·K)), the initial volume (Vi = 10 L), and the final volume (Vf = 20 L).
Step 2: Use the formula for change in entropy (ΔS) for an ideal gas during isothermal expansion: ΔS = nR ln(Vf/Vi).
Step 3: Substitute the values into the formula: ΔS = 1 * 8.314 * ln(20/10).
Step 4: Calculate the natural logarithm: ln(20/10) = ln(2).
Step 5: Calculate ln(2) which is approximately 0.693.
