What are the formal and informal power of the senate? How do you know?

We know because it is in Article 1 of the Constitution

Formal Powers:

• Impeachment-holding trials
• Confirmation of Nominations
• Approve Treaties made by the Executive branch by 2/3 vote
• Expulsion someone else in the Senate
• Censure
• Investigations
• Contested Senate Elections

Informal Powers:

• Filibuster and Cloture
• Power of Persuasion
• Executive Agreements
• Issue Executive Orders
• Issue Signing Statements
• Bureaucracy
• Legislative Proposal

The senate has more things going on that is not in the Constitution