Hey,

Out of 70, you need to score atleast 23 marks in theory alone to be declared as pass in the Central Board of Secondary Education examination.

This is applicable to chemistry and all other subjects which has a paper of total 70 marks. The other 30 marks are for practical examination.

Hey,

The passing marks for chemistry in CBSE for the theory paper is 33% so that is 23 out of 70.

Hope it helps.

Thank You