One power that is not an expressed power of Congress is the power to grant reprieves and pardons. This power is given to the President of the United States. The President can also make war even when Congress has not declared war.
Expressed powers are written in the Constitution, and implied powers are those that are considered necessary to carry out expressed powers. Congress holds most expressed powers, including the power to collect taxes, declare war, borrow money, establish post offices and issue patents. Congress’s implied powers come from the General Welfare clause in the Preamble of the Constitution, the Necessary and Proper Clause and the Common Clause in the Constitution itself.