The vice president. When the office of vice president is vacant it is the president pro tempore.
Yes and no. First, to be impeached does NOT mean to be removed. Also, not all elected officials can be impeached, for example the president, VP and federal judges CAN be impeached. If an elected official is impeached, it means he/she is formally charged with one or more crimes. The US House of Representatives impeaches with a majority vote. The impeached official must now stand trial in the US Senate. The 100 Senators act as the jury and the VP, as President of the Senate, acts as the judge, unless the person on trial is the president or himself/herself. In this case the Chief Justice of the Supreme Court acts as the judge. A 2/3 vote of the Senate is needed to convict the accused and remove him/her from office.
The Vice-President of the United States acts as President of the US Senate, to break a tie if the Senate is split 50-50.
(In the U.S) The President Pro Tempore usually acts as president of the senate. Currently, this is Daniel Inouye.
The Vice-President
The Vice President of the United States acts as the President of the Senate, but he has no vote except to break ties. This is his only official role. Only the first few Vice Presidents actually acted as the President of the Senate; the VP only shows up when the vote is likely to be a tie. The rest of the time, the majority leader of the Senate acts as the "President Pro Tem" (or "pro tempore", "of the moment") and manages the day to day business of the Senate.
In the US, the elected official who is, per the US Constitution, the Commander-In-Chief of the Armed Forces is the President.
According to the constitution, the House of Representatives has the power to impeach federal officials (even the president). The Senate acts as the jury, and (in presidential cases) the Chief Justice acts as the judge.
He acts as the President of the US Senate.
The US Vice President performs the duty as the President of the Senate. He or she has no vote except in situations where there is a tie in votes. The Vice President is then allowed to vote to settle the issue at hand.
The US Senate acts as the jury and tries any impeachment cases. When the House of Representatives accuses an official of a crime, the US Senate decides whether or not the official is guilty.
The US Senate of the legislative branch acts as a jury in an impeachment trial against the the President.
The Vice President of the United States is the President of the Senate.. He can not vote unless there is a tie but he can vote to break a tie. Such is his only power.