Name the bone that articulates with the manubrium?

The sternum articulates (comes together) with the cartilages of the first seven ribs and with the clavicle (collar bone) to form the middle part of the anterior (front) wall of the thorax (chest).

The sternum consists of three portions: the manubrium (the upper segment of the sternum, a flattened, roughly triangular bone), the corpus or body of the sternum, and the xiphoid process (the little tail of the sternum than points down). These three portions of the sternum arise as separate bones and may fuse partially or completely with one another.

 The wesite will help you alot http://en.wikipedia.org/wiki/Collar_bone