Fakhar Zaman (31) was set but lost his footing trying to sweep Kuldeep Yadav (2/41 in 10 overs) to get leg before.
Babar Azam was run-out when his skipper got a call for single wrong as Pakistan were reduced to 58 for three.
Yuzvendra Chahal (2/46 in 9 overs) got his first wicket by trapping Imam ul Haq (10) in front of the stumps.
Pakistan innings was built around Shoaib Malik's defiant knock of 78 in 90 balls and his 107-run partnership for the fourth wicket with captain Sarfraz Ahmed (44 in 66).
One of the most fearsome opening pairs in ODI format, Rohit-Dhawan combination were helped by some ordinary bowling from Pakistan with equally sloppy fielding compounding their woes.
Pakistan were sloppy in the field with Imam dropping a sitter off Rohit Sharma when he was on 10.
Dhawan scored 114 before he was run out.
Rohit scampered home for a double to complete his 19th ton and on the way also completed 7000 runs in ODI format.
It was India's largest ODI victory margin in terms of wickets against Pakistan, surpassing its previous best of eight wickets in the group stage of the same tournament and on five other occasions.