The 5-chloro-8-hydroxy-quinolinium cation in the the title ion pair, C(9)H(7)ClNO(+)·NO(3) (-), is approximately coplanar with the nitrate anion [dihedral angle = 16.1 (1)°]. Two ion pairs are hydrogen bonded (2 × O-H⋯O and 2 × N-H⋯O) about a center of inversion, generating an R(4) (4)(14) ring.
* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.