Why was the Missouri Compromise of 1820 passed? Where did the Missouri

Compromise allow slavery? Where was slavery deemded off limits according to this

compromise?

In 1820, amid growing sectional tensions over the issue of slavery, the U. S. Congress passed a law that admitted Missouri to the Union as a slave state and Maine as a free state, while banning slavery from the remaining Louisiana Purchase lands located north of the 36º 30' parallel.