Did the compromises that Congress made effectively address slavery and sectionalism?

The answer is no.

The Missouri Compromise (1820) allowed Missouri to enter as a slave state, Maine to enter as a free state, and established the 36'30 line. This stated that anything above this line would be territories without slavery and anything below this line would allow slavery. This was a short term solution and did not work for long, as the US kept adding territory. A lot of this territory was above the line, making it so that there would be more slave free territories than slave territories. This upset southern politicians so they made another compromise.

The Compromise of 1850:

1) Added California as a free state

2) Banned the slave trade in Washington D. C.

3) Implemented a fugitive slave law

4) Implemented "popular sovereignty" in the New Mexico and Utah territories.

This idea also did not work, as northerners ignored the fugitive slave law which was supposed to make northerners return runaway slaves to their owners in the south.