Which amendment to the Constitution of the United States required the electoral college to specify separately who would be president and vice president?

The amendment that required the electoral college to specify separately who would be president and vice president is the 12th Amendment. Ratified in 1804, this amendment was introduced in response to issues that arose during the elections of 1796 and 1800, where the electoral process led to complications and conflicts in determining the president and vice president.

Prior to the ratification of the 12th Amendment, each elector cast two votes for president; the candidate with the majority of votes would become president, while the runner-up became vice president. This system resulted in situations where candidates from opposing parties could end up in the top two positions, leading to significant discord. The 12th Amendment remedied this by establishing distinct ballots for the office of president and vice president, ensuring that voters could explicitly choose their preferred candidates for each position. This change aimed to create a more straightforward and coherent electoral process, which is still in place today.

The other amendments mentioned do not pertain to the electoral college or its procedures. The 10th Amendment focuses on states' rights, the 15th Amendment prohibits denying the right to vote based on race, and the 22nd Amendment limits presidential terms.