Chemistry Section Marking Scheme:

The Chemistry section of the NDA exam consists of questions based on various topics such as Physical Chemistry, Inorganic Chemistry, and Organic Chemistry. Each question carries 4 marks, and there is a negative marking of 1/3 marks for each incorrect answer. The detailed marking scheme for the Chemistry section is as follows:

Physical Chemistry:
- This section usually comprises questions related to concepts such as stoichiometry, atomic structure, chemical bonding, states of matter, thermodynamics, and electrochemistry.
- Each question from this section carries 4 marks.
- For correct answers, candidates will be awarded 4 marks.
- For incorrect answers, 1/3 mark will be deducted.

Inorganic Chemistry:
- Inorganic Chemistry questions generally cover topics like periodic table, chemical reactions, coordination compounds, metallurgy, and chemical analysis.
- Each question from this section carries 4 marks.
- For correct answers, candidates will be awarded 4 marks.
- For incorrect answers, 1/3 mark will be deducted.

Organic Chemistry:
- This section includes questions related to organic compounds, nomenclature, reactions, and their applications.
- Each question from this section carries 4 marks.
- For correct answers, candidates will be awarded 4 marks.
- For incorrect answers, 1/3 mark will be deducted.

General Science Section Marking Scheme:

The General Science section of the NDA exam includes questions from Physics, Biology, and Environmental Science. Each question carries 4 marks, and there is a negative marking of 1/3 marks for each incorrect answer. The detailed marking scheme for the General Science section is as follows:

Physics:
- Physics questions in this section cover topics such as mechanics, optics, thermodynamics, electricity, and magnetism.
- Each question from this section carries 4 marks.
- For correct answers, candidates will be awarded 4 marks.
- For incorrect answers, 1/3 mark will be deducted.

Biology:
- Biology questions generally cover topics such as cell biology, genetics, human physiology, plant physiology, and ecology.
- Each question from this section carries 4 marks.
- For correct answers, candidates will be awarded 4 marks.
- For incorrect answers, 1/3 mark will be deducted.

Environmental Science:
- This section includes questions related to environmental issues, pollution, conservation, and sustainable development.
- Each question from this section carries 4 marks.
- For correct answers, candidates will be awarded 4 marks.
- For incorrect answers, 1/3 mark will be deducted.

It is important for candidates to thoroughly prepare for each topic and practice solving previous years' question papers to get acquainted with the exam pattern and marking scheme.