Unknown bacteria determined to be Alcaligenes faecalis because of its morphological, physiological and metabolic properties. In a laboratory setting, it often becomes necessary to identify an unknown organism. In this experiment, researchers classified an unidentified bacterium based on its physical structure, colony morphology, optimal conditions and metabolic properties. A Gram stain using crystal violet, iodine, and safranin and a simple stain using methylene blue characterized the organism’s cell wall. Cultural behavior was classified by inoculating the organism onto nutrient agar and incubating it at 37° C for 48 hours, and observing its behavior, as well as using SIM medium to test for motility. Optimal growth temperature was determined by incubating nutrient broths of the organism at 25° C and 37° C, and optimal pH was tested by inoculating broths with pHs of 3, 7, and 10. Fluid thioglycollate medium determined the organism’s oxygen requirements. The metabolic profile was created by inoculating the bacterium into broths containing glucose, lactose, mannitol, and citrate and incubating the tubes at 25° C for 48 hours, then observing it for color change. Oxidative metabolic tests for oxidase and catalase were also performed using an oxidative reagent and hydrogen peroxide, respectively. The Enterotube II System was used to further classify its metabolic profile. The stains revealed that the bacterium was a Gram-negative bacillus. The organism was shown to be non-motile and grows best at a pH of 10 and a temperature of 25° C, making it an alkaliphilic mesophile. The oxidation and fermentation tests showed that the organism is an oxidase-positive, catalase-positive aerobe that does not ferment sugars or metabolize citrate. The Enterotube II test results showed that the bacterium is not an Enterobacterium. In light of these attributes, the organism belongs in