L8 - CSIR NET Life science Biochemistry [Basics of Thermodynamics] | IFAS I GATE I IIT JAM

Introduction

This tutorial covers the basics of thermodynamics relevant to biochemistry, as presented in the "L8 - CSIR NET Life Science Biochemistry" video by IFAS. Understanding thermodynamics is crucial for students preparing for exams like CSIR NET, GATE, and IIT JAM, as it lays the foundation for studying biochemical processes.

Step 1: Understand Thermodynamics

• Define thermodynamics as the branch of physics that deals with heat, work, and energy transformations.
• Recognize the relevance of thermodynamics in biochemical reactions and life processes.

Step 2: Learn Energy Units

• Familiarize yourself with the units of energy, including:
  • Joules (J)
  • Calories (cal)
  • Electronvolts (eV)

Step 3: Differentiate Between System and Surroundings

• Define the universe in thermodynamics as:
  • Universe = System + Surroundings
• Identify different types of systems:
  • Closed system: No exchange of matter, but energy can be exchanged.
  • Open system: Both matter and energy can be exchanged.
  • Isolated system: No exchange of matter or energy.

Step 4: Explore the First Law of Thermodynamics

• State the First Law: Energy cannot be created or destroyed, only transformed.
• Understand the concept of internal energy (E or U):
  • This is the total energy contained within a system.

Step 5: Recognize State Functions

• Define state functions as properties that depend only on the state of the system, not how it reached that state. Examples include:
  • Internal energy
  • Enthalpy
  • Entropy

Step 6: Dive into Entropy

• Define entropy as a measure of disorder or randomness in a system.
• Discuss its role in biochemical systems, emphasizing that:
  • Entropy helps predict the spontaneity of processes.

Step 7: Understand the Second Law of Thermodynamics

• State the Second Law: In any energy transfer, the total entropy of a closed system can never decrease.
• Recognize that biological systems are not exceptions to this law; they also increase entropy overall.

Step 8: Learn About Gibbs Free Energy

• Define Gibbs free energy (G) as a thermodynamic potential that measures the maximum reversible work obtainable from a system at constant temperature and pressure.
• Use the Gibbs free energy equation:

  G = H - TS
  

  Where:
  • H = enthalpy
  • T = temperature in Kelvin
  • S = entropy

Conclusion

This tutorial has introduced you to the fundamental concepts of thermodynamics in biochemistry, focusing on definitions, laws, and applications. To deepen your understanding, consider exploring these concepts further through practice problems or additional readings. Engaging with study groups or discussions can also enhance your grasp of thermodynamic principles in biochemical contexts.