UA 2197 then CA 3174 at O'Hare
Houston → Chicago → Guangzhou
Timetable, Chicago time
21:40UA 2197 from Houston at the gate
13:40CA 3174 to Guangzhou leaves the gate
16 h apart on the timetable, overnight
CA 3174 leaves 16 h after UA 2197 arrives on the timetable: more than half a day, so not a connection we count.