Reasonable? See Scrovegni chapel during trip from Venice to Ravenna?

Sure
It’s about 2.5 hours by regional train from Padova to Ravenna-change in Bologna or Ferrara (Ferrara is easier)
Or there are fast train options that are a bit quicker-still always a regional to Ravenna ( runs hourly from Bologna)

You could spend most of day in Padova and still get to Ravenna by dinner time-assuming you are staying the night or 2 there?

We found 1 time slot to be sufficient
YMMV

Make sure you get Chapel tickets in advance. Safe travels!

Padua and Ravenna each have enough to keep you busy for more than one full day. How much total time do you have between departure from Venice and departure from Ravenna?

Padova is an easy train ride from Venice, trains run often and regularly. When you get to Padova take a taxi to the chapel. I also recommend a visit to the close by archaeological museum, including the journals of Belzoni who conducted some of the first excavations in Egypt. There are also exhibits relating to Roman Padua. The University is interesting especially the anatomy theatre. There are lots of bars and restaurants around the University,.

Check the Trenitalia website for trains to Revello…there seems to be one that leaves Padova at around 5.30 and gets to Ravello at 8.30 with a change.

Thank you

Given our time constraints, my wife and I weren't interested in Venice (when planning for our 2020 trip which was cancelled due to lockdown).
Our friends wanted to go there.

My wife and I are thinking of us all flying into Venice (AM arrival), spending two nights there. To Then seeing Padua on the way to Ravenna.
Two nights in Ravenna.
We're debating about all the stops/stays ...

My wife and I only have three things on our bucket list
1) Ravenna mosaics
2) a Thermal spring like Bagno San Filippo
3) the Scrovegni chapel

Venice to Padova in little as 28 minutes. The Musei Civici, where the chapel is located, is worth exploring. You also need to see the Prato Della Valle, the largest square in Italy; one of the largest in Europe. The staffed luggage facility for storing your bags is right across from the ticket office.

Honestly, I’d stay in Padua, and day trip to Venice. Many trains per hour each way. Padova is much cheaper, friendly, and not as crowded. Train ride is less than half an hour to Venice and cheap. Restaurants are also very good, and not nearly as pricy. You could leave early morning and return late in the day, or whenever. Also can take train westward from Padova to Vicenza for day trip and see the beautiful 14th century architecture on a day trip. This would cut your costs in 1/3 and afford you more sights, and a more relaxing trip. Venice can be overrun, flooded, and crazy.

It's really not a problem to find quiet areas of Venice to wander in--if you have time to do that after seeing what you judge to be your personal must-see sights (which, it's true, may be beyond mobbed). Commuting from Padua (or Venice-Mestre for that matter) gives you less time in Venice to enjoy its quiet corners. You lose out on some of the early morning and late evening time when Venice is at its best, and all your time in Venice falls into the day-tripping hours when parts of the city are overrun. I can't dispute that staying outside Venice would save money on lodging, but the same argument would be true for staying out in the farther suburbs of Rome.

I like Padua a lot, but it's not a substitute for Venice.

The point about Venice is to be there early morning and late evening.

The Chapel is less than 1 K from the train station. We bought our tickets for the Chapel in the train station. However, when we went to the Chapel, we could have purchased tickets right then and gone in immediately. We did not do the back-to-back, but that would have been great. The Chapel is well worth the trip.

You don't say when you will be going. We were there Sept 17 2022, and getting tickets to ANYTHING in Italy was easy without a delay. We got tickets for the mosaics in Ravenna, and went in to the first one immediately. We also enjoyed the mosaics. If you know a little Italian history of the 4-6th centuries, the mosaics make more sense. The Gothic (Vandal?) emperor Theodoric was Emperor of Rome, and the center of government was actually in Ravenna.

We went directly from Ravenna to Padova. It was not a long train ride.