The Reds made three changes from the goalless draw in the first-leg, as shot-stopper Caoimhin Kelleher replaced the rested Alisson, while Curtis Jones was recalled alongside a rare start for teenage forward Kaide Gordon, while the Gunners recalled Martin Odegaard, Emile Smith Rowe and Takehiro Tomiyasu.
Mikel Arteta's charges came close to having a perfect start in the sixth minute after Alexandre Lacazette curled a free-kick towards the top corner that was tipped into the post by Kelleher.
However, Diogo Jota eventually broke the deadlock for Liverpool in the 19th minute and also on aggregate with a low strike from the edge of the box after making a good turn from Trent Alexander-Arnold's pass.
Arsenal were working their way back into the game, forcing Jurgen Klopp's troops to retreat but they could not find a way through a compact defence and went to the half-time break trailing by a lone goal.
The Reds had a quick start in the second stanza, as Gordon missed a sitter after a square pass from Jota and Ibrahima Konate crashed the post on the hour-mark with a header from Alexander-Arnold's corner.
Arteta made a double change in the last quarter of an hour as Thomas Partey replaced Smith Rowe in a tactical move and Eddie Nketiah came on for Lacazette for fresh legs upfront.
Jota put the game to bed for Liverpool just after that, as he latched onto a ball over the top by Alexander-Arnold and chipped his effort over goalkeeper Aaron Ramsdale and although the goal was initially disallowed for offside, it was eventually given by the Video Assistant Referee (VAR).
The Gunners finished the game with ten men after Partey was red-carded in the last minute for a lunging tackle on Fabinho, as the Reds cruised to the final with a 2-0 aggregate win to setup a meeting with Chelsea in the final.