My wife and I have both killed black bear with a 300 Wby Mag
and handloads with 180 Nosler Partitions. I have also killed them with 450/400 3 1/4" and 9,3x74R double rifles.
Your 35 Whelen should be about perfect.
The bears killed with the 300mag needed more than one shot... not so with the 400 and the 9,3.