in 1820 a series of measures were put in place to improve the conditions of slaves was called

The Missouri Compromise.

what isthe correct sequence of events when it comes to the abolition of slave trade,emancipation and apprenticeship

The correct sequence of events when it comes to the abolition of slave trade, emancipation, and apprenticeship varies by country. Here are a few examples:

In the United States:

1. Abolition of the international slave trade in 1808.
2. Emancipation of slaves through the 13th Amendment in 1865.
3. No official apprenticeship period.

In the British Empire:

1. Abolition of the international slave trade in 1807.
2. Emancipation of slaves through the Slavery Abolition Act in 1833.
3. Apprenticeship period from 1833-1838.

In Brazil:

1. Abolition of the transatlantic slave trade in 1831.
2. Emancipation of slaves through the Lei Áurea in 1888.
3. No official apprenticeship period.

In Cuba:

1. Abolition of the international slave trade in 1808.
2. Emancipation of slaves through the Pact of Zanjón in 1878.
3. Apprenticeship period from 1880-1886.

It's important to note that even after the abolition of slavery and apprenticeship periods, systemic racism and inequalities persisted in each of these countries.

The series of measures that were put in place in 1820 to improve the conditions of slaves was not specifically called anything in particular. However, during this time period, there were various efforts and reforms aimed at ameliorating the treatment of slaves.

One notable measure that was enacted in the early 19th century was the prohibition of the international slave trade in the United States in 1808. This meant that importing slaves from Africa was illegal, which was a step towards reducing the number of enslaved people.

Additionally, there were some individual efforts by slave owners and legislators to improve the lives of their slaves. Some slaveholders implemented more humane treatment of their slaves, providing them with better housing, clothing, and food. Some states also passed laws that regulated the treatment of slaves, such as restrictions on physical punishment.

It is important to note, however, that these measures were often limited in scope and did not lead to significant improvements for the vast majority of enslaved individuals. Slavery itself was a deeply unjust institution, and any reforms enacted during this time were usually insufficient to truly address the systemic oppression faced by enslaved people.

To find more detailed information on the measures put in place to improve the conditions of slaves in 1820, it would be helpful to consult historical documents, books, or scholarly articles that cover the topic of slavery during that time period.