JAM

No, you can't as you know you have failed in chemistry. You'll not get admission in any NIT or any B.Tech college.

Eligibility criteria:
IIT JAM 2018 Subject-wise cut-off is mentioned below. Please check, if you made the cut from the marks mentioned below. In Physics, qualifying marks for general category are 19.51 while for SC/ ST/ PWD, it is 9.76. For Physics Paper/
In Chemistry, qualifying marks for General Category students are 14.79 and 7.39 for SC/ST/PWD. For Chemistry Paper of IIT JAM 2018. In Mathematics, qualifying marks for General Category are 23.35 and 11.68 for SC/ST/PWD. Based on IIT JAM Result 2018, candidates will be admitted to institutes if they fall in above eligibility then you are eligible.
All the best.

Please refer to the link provided below for a detailed list of colleges which accept IIT JAM 2018 scores/ranks for admission. You can select college (s) from this list where you would feel comfortable pursuing M.Sc. in chemistry. Regards. https://www.shiksha.com/science/articles/colleges-accepting-iit-jam-scores-ranks-for-admission-blogId-13971.

Colleges accepting IIT JAM 2018 scores/ranks for admission are mentioned at the link provided below. Candidates are informed of the total number of seats available for different M.Sc courses offered at all participating institutes. A total of 15 IITs, 16 NITs, and two Centrally Funded Technical Institutes (CFTIs) accept JAM scores for M.Sc admissions:
https://www.shiksha.com/science/articles/colleges-accepting-iit-jam-scores-ranks-for-admission-blogId-13971