Kansas is almost entirely in the Central Time Zone, with the exception of Greeley, Hamilton, Sherman, and Wallace western counties which are in the Mountain Time Zone. Kearny County had been split between Central and Mountain zones but changed completely to Central.
IANA time zone database
The 2 zones for Kansas as given by zone.tab of the IANA time zone database. Columns marked * are from the zone.tab.
References
Time in Kansas Wikipedia(Text) CC BY-SA