Richter, who will serve as speaker until February's general student body elections, defeated District 19 representative and former Speaker Pro Tem Matt O'Brien.
"This year, there's been something inside me that's said, 'This is what I can do to give back to the student body,'" she told Congress members before the vote.
Larson had to resign from his position because he is graduating at the end of the semester.
Richter served on the 82nd session of Congress two years ago and has worked as Congress' Student Affairs Committee chairwoman while representing District 15 this year.
As she sought support from Congress members Tuesday night, Richter said she wanted to use her new position to help individuals realize their goals.
The new speaker also promised to maintain many of the ideals that have characterized this session of Congress' leadership.
For one, she said, being responsible with financial matters as Congress allocates funds to student organizations will be a top priority.
"We have to keep an eye on what's going on with finances," she said.
Richter stressed to Congress the importance of its future responsibilities and noted that in January, Congress will see a report on UNC's ongoing judicial review from the Committee on Student Conduct.