Mendeleyevsk (Russian: Менделе́евск; Tatar Cyrillic: Менделеев, Latin: Mendeleyev) is a town and the administrative center of Mendeleyevsky District of the Republic of Tatarstan, Russia, located on the Toyma River, 238 kilometers (148 mi) east of Kazan. Population: 22,075 (2010 Census preliminary results); 22,027 (2002 Census); 18,085 (1989 Census).