The Compromise of 1850 was more favorable in preserving the nation compared to the Missouri Compromise of 1820. The Compromise of 1850 addressed the issue of slavery in the newly acquired territories from the Mexican-American War, allowing for a more balanced approach by admitting California as a free state and allowing slavery in the Territory of New Mexico. It also included measures such as banning the slave trade in the District of Columbia and implementing a more stringent Fugitive Slave Law.
In contrast, the Missouri Compromise only banned slavery in the Louisiana Territory north of the 36° 30’ parallel, with exceptions made for the state of Missouri. While it did address the issue of slavery in new territories to some extent, it only focused on a specific geographical area and did not provide a comprehensive solution like the Compromise of 1850.
Therefore, the Compromise of 1850 was more favorable in preserving the unity of the nation by addressing the issue of slavery in a broader context and implementing measures to maintain a delicate balance between free and slave states.