Bond Angle
A bond angle is a geometrical angle between two bonds originating from the same central atom in a covalently bonded molecule, measured in degrees (o).

A bond angle is a geometrical angle between two bonds originating from the same central atom in a covalently bonded molecule, measured in degrees (o).

A benzyl, abbreviated as Bn, refers to the phenylmethyl group (C6H5-CH2-), consisting of a benzene ring attached to a methylene (-CH2-) group.
The random collisions of the colloidal particles (dispersed phase) with molecules of the dispersion medium (colloidal sol) that results in a zig-zag movement of the colloidal particles, when observed under an ultramicroscope, is known as the Brownian Motion.