Congress passed macon's bill no. 2 in 1810 to replace the unsuccessful non-intercourse act of 1809. what did this bill entail for us trade?

The bill entailed that the United States would remain neutral in the Napoleonic wars. The bill was introduced because the British and France navy used to seize ships from Americans. The bill stated that if a party would stop taking ships, Americans would in return stop trading with the opposing side, which meant "if you don't take our ships, we won't trade with your opponents". 

Because the south needed slavery to run it's economy and they could hardly endorse one kind of freedom and not the other. The declaration is a summary of all the injustices endured by the colonies, but the largest one of all was the slavery inflicted on the colored by landowners.

It would take a civil war to resolve the issue of slavery. At the time of the Declaration it was a completely non negotiable point.