George Horne went over for two tries and after the game told Channel 4: "Obviously we were fairly disappointed after last week.
"We knew we had to come out and be physical and aggressive and I think we did that tonight."
Horne set the ball rolling after just 76 seconds, combining with fly-half Adam Hastings to cross for his first international try.
Blair Kinghorn, Stuart McInally and Magnus Bradbury all touched down before Horne went over for his second try late in the first half to establish a commanding 36-3 lead at the break.
Tomas Lezana and Matias Orlando hit back for the Pumas in the second period but Dougie Fife try and a Peter Horne penalty ensured there was never any hint of a comeback.
"It was class. We put on a good show," Horne added.
"It was great going up by 20 points at the start. It put us in a great position to play the territory game.
"When the rain came down we just had to play smart, play in the right areas and we did that really well. I thought Adam (Hastings) was outstanding at 10.
"It was a massive honour to get my first cap last week and it was even sweeter getting the victory tonight. It was great fun."
Full-back Stuart Hogg said it was satisfying to round off the summer tour on a high, and says some of the younger players in the squad have laid down a marker for future selection by head coach Gregor Townsend.
"We worked incredibly hard for that," Hogg told Channel 4. "We were bitterly disappointed by last week's result so it was great to finish off on a high and we go home happy men.
"The younger boys are pushing us and it's great for Scottish rugby. They're coming in full of energy and ready to learn. It's only going to put us in good stead. We'll have a good night tonight."