Hello.

There are several sites from which you can download the PDFs of chemistry books for free. If you want to download NCERT book of chemistry , then you can download the NCERT app from playstore. Else google for free sites.

Here is a link below to one such site from where you can download the PDFs of chemistry book and notes: http://www.freebookcentre.net/Chemistry/Chemistry-Books-Online.html

Hope this helps!