Hello Student
NIOS formerly known as NOS was established in the month of November, 1989. It is the largest National open schooling system of education in the world. The process of demand examination is that when the candidates will feel ready for examination candidate will go straight to the examination centre and appear for examination. Term of examination was introduced and become popular as ODE. NIOS re introduce this process of examination that is ODE in the secondary level in the year of 2005. Now it has been introduced in the senior secondary level also. The previous years question pattern of chemistry for the class of 12 of NIOS may be had of NIOS official website : http://www.nios.ac.in>previous -year-question paper.
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