"Chemicals React" Is A Pop Rock Song Written And Recorded By American Pop Rock Duo Aly & AJ For The Deluxe Edition Reissue Of Their Debut Album Into The Rush 2005 . The Michalka Sisters Co-Wrote The Song With Antonina Armato And Tim James Of Production Duo Rock Mafia Who Also Produced The Track. It Was The Second Mainstream Single From Into The Rush And Seventh Overall Single Released To Radio By Hollywood Records On June 27 2006.