say any important chapter of jee gun shoot questions to get atleat 120+ marks

Dear Aspirant,

From your question language it looks like you want the important chapters for the JEE examination. Here are some important chapter:-

Integral Calculus,
Three Dimensional Geometry,
Co-ordinate Geometry,
Sets, Relations & Functions,

Laws of Motion, Kinematics,

Work, Energy & Power,

Gravitation, Rotational Motion,

Thermodynamics,

Electrostatics, Oscillations & Waves,

Magnetic Effects of Current & Magnetism,

Current Electricity,

Electromagnetic Induction & Alternating Currents,

Optics, Electromagnetic Waves,

Dual Nature of Matter & Radiation,

Atoms & Nuclei,

For chemistry, I suggest you must go with organic chemistry wholly.

Purification & Characterisation of Organic Compounds,

Organic Compounds Containing Halogens,

Hydrocarbons,

Organic Compounds Containing Oxygen,

Polymers,

Organic Compounds Containing Nitrogen,

Bio Molecules,

Principles Related to Practical Chemistry,

Chemistry in Everyday Life.

Hope this helps. Thank you.