<prompt> Which of the following poisoning is demonstrated by Kunkels test?LeadCuSO4CODhatura  <response>: Kunkels test or tannic acid test: If tannic acid is added to blood it remains cherry-red in CO poisoning, where oxyhemoglobin turns deep brown. Hoppe-Seylers test is also used to identify CO poisoning. Few drops of blood are added to a solution of 10 sodium hydroxide. Normal blood turns brownish-green, but if CO is present, the color will remain pink. Ref: The Essentials of Forensic Medicine and Toxicology by KS Narayan Reddy, 27th edition, Page 555. 