Powers of the Legislative Branch(Congress): Article I describes the powers as Congress can Make laws, Declare war, Raise and provide public money and oversee its proper expenditure, Impeach and try federal officers, Approve presidential appointments, Approve treaties negotiated by the executive branch, and Oversight and investigations.
Powers of the Executive Branch(President): Article II describes the powers of the President as he can carry out and enforce laws, veto bills passed in Congress, call Congress into special session, serve as commander in chief of the armed forces, receive leaders and other officials of foreign countries, make treaties with other countries, appoint heads of executive agencies, and pardon or reduce the penalties against people convinced of federal crimes.
Powers of the Judicial Branch(Supreme Court): Article III describes the Supreme Court as having the power to interpret the law, determine the constitutionality of the law, and apply it to individual cases. They can interpret the laws but cannot enforce them.
Checks and Balances: A system in which each branch of government can "check" or control, the actions of the other branches. It keeps each branch from becoming too powerful. Essentially each branch is kept in check by each other and to an extent, the people.
Separation of Powers: The institutional arrangement that assigns judicial, executive, and legislative powers to different persons or groups, thereby limiting the powers of each. The Checks and Balances and Separation of Powers go hand in hand. They work together to keep power limited so the three Branches won't overpower one another.
Hope this helps. (sorry it took so long)
