What were the main problems with the articles of confederation that led to the constitutional convention of 1787? how did the national government under the constitution differ from the articles of confederation?

The main problem of Article of Confederation was the loose bond of friendship among the states creating a weak central government and almost powers lies with State governments which led to Constitutional Convention in Philadelphia in 1787 to address the problems of weak central government under Article of Confederation. National government under the constitution differs from the articles of confederation because Constitution emphasize on the need of having strong federal government that could unite states which could be fair and representative as a part of one great nationality.

necessary and proper clause. the congress shall have power to all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states, or in any department or officer thereof.