How do I undo a close of a tab?

I upgraded from Galaxy Mega to Galaxy S6 Edge +. There seems to be no undo button. In Galaxy Mega, when I use Chrome, I can undo close tabs. However, in S6E+, each tab opened in chrome is part of the list of running apps as seen when pressing the Recent button on the lower left. How can I undo a close of of a tab in chrome? Can I undo a close of an app?