Section-wise Mark Distribution in IIT JAM Chemistry:

Section A: Physical Chemistry
- This section consists of topics related to the fundamental principles and concepts of Physical Chemistry.
- It covers topics such as Atomic and Molecular Structure, Thermodynamics, Electrochemistry, Chemical Kinetics, and Solid State.
- The weightage of this section in the IIT JAM Chemistry exam is approximately 25%.
- The questions in this section are generally theoretical and require a strong understanding of the basic principles.

Section B: Inorganic Chemistry
- Inorganic Chemistry deals with the study of elements, compounds, and their properties.
- This section includes topics such as Periodic Table and Periodicity in Properties, Main Group Elements, Transition Metals, Coordination Chemistry, and Organometallics.
- The weightage of this section in the IIT JAM Chemistry exam is approximately 35%.
- The questions in this section can be both theoretical and analytical, requiring a good knowledge of various concepts and trends in the periodic table.

Section C: Organic Chemistry
- Organic Chemistry focuses on the study of carbon compounds and their reactions.
- This section includes topics such as Basic Concepts in Organic Chemistry, Organic Reaction Mechanisms, Stereochemistry, Pericyclic Reactions, and Biomolecules.
- The weightage of this section in the IIT JAM Chemistry exam is approximately 40%.
- The questions in this section are generally based on reaction mechanisms, functional group transformations, and structure determination.

Section D: Mathematical Concepts
- This section tests the mathematical aptitude of the candidates in relation to Chemistry.
- It includes topics such as Differential Calculus, Integral Calculus, Ordinary Differential Equations, Probability and Statistics, Matrices and Determinants, and Vector Algebra.
- The weightage of this section in the IIT JAM Chemistry exam is approximately 15%.
- The questions in this section are generally numerical and require the application of mathematical concepts to solve problems.

Overall Mark Distribution:
- The IIT JAM Chemistry exam consists of a total of 60 questions.
- Each question carries 1 or 2 marks, depending on the section.
- Section A consists of 15 one-mark questions and 20 two-mark questions.
- Section B consists of 15 one-mark questions and 20 two-mark questions.
- Section C consists of 15 one-mark questions and 20 two-mark questions.
- Section D consists of 10 one-mark questions and 5 two-mark questions.
- The total marks for the exam are 100.

Note: The weightage and number of questions may vary from year to year, so it is important to refer to the official IIT JAM Chemistry syllabus and exam pattern for the most accurate and updated information.