Hull will begin their debut European campaign with a tie against either AS Trencin of Slovakia or Serbia's Vojvodina.
The 2014 FA Cup finalists were in the hat for Friday's Europa League third qualifying round draw and look most likely to meet the Slovakian side, who have a 4-0 lead over Vojvodina from the first leg of their second-round tie.
If Motherwell come through their second-round encounter with Icelanders Stjarnan - the first leg of which finished 2-2 in Scotland - they will take on Nomme Kalju of Estonia or Lech Poznan of Poland.
Aberdeen will have a tough task ahead if they progress from their tie against FC Groningen, with Spain's Real Sociedad lying in wait for the winners. The Dons fought out a 0-0 first-leg draw with the Dutch outfit at Pittodrie on Thursday.
Meanwhile, Scotland's other participants St Johnstone will play Zestafoni of Georgia or Spartak Trnava of Slovakia should they get past Luzern following a 1-1 first-leg draw in Switzerland.