IIT JAM Chemistry course is an advanced level course that builds upon the concepts learned in 11th and 12th class chemistry. While there are some similarities between the two, there are also significant differences that make IIT JAM Chemistry a more challenging and specialized program of study.

Similarities
- Both 11th and 12th class chemistry and IIT JAM Chemistry cover fundamental concepts of chemistry, such as atomic structure, chemical bonding, and thermodynamics.
- Both courses also cover organic, inorganic, and physical chemistry.

Differences
- IIT JAM Chemistry goes into much greater depth on these topics than 11th and 12th class chemistry, and also covers additional advanced topics, such as quantum mechanics, spectroscopy, and statistical mechanics.
- IIT JAM Chemistry also requires a greater level of mathematical proficiency than 11th and 12th class chemistry, as it involves complex equations and calculations.
- The laboratory work in IIT JAM Chemistry is also more advanced and specialized than in 11th and 12th class chemistry, with a greater emphasis on experimental design and data analysis.

Conclusion
In conclusion, while there are some similarities between 11th and 12th class chemistry and IIT JAM Chemistry, the latter is a much more advanced and specialized program of study. It requires a greater level of mathematical proficiency and covers more advanced topics in greater depth. The laboratory work is also more specialized and advanced, making IIT JAM Chemistry a challenging and rewarding program for those who are passionate about chemistry.