Spiked chain trip / disarm attacks

[Seems]

One of my players decided to take the spiked chain as a exotic weapon feat, and I just want to make sure I know how it works.

Am I correct in assuming that the trip/disarm attacks are separate attacks that are not reliant on a successful "regular" attack roll first? In other words, if you want to disarm someone, you make your CMB attack and if successful you inflict no damage but disarm your opponent?

[Java Man]

Correct.

[Seems]

Java Man wrote:

Correct.

Thanks Java Man!

[Nefreet]

Plus, when you use a weapon with the Disarm property, you get a +2 bonus on Combat Maneuver Checks to disarm an enemy.