QUESTION: How many ways can the intrinsic magnetism of an electron in a 4d orbital be oriented? A. 2, B. 3, C. 5, D. 10 In addition to the magnetism generated by the motion of an electron around the nucleus, experimental evidence suggest that electrons also have an intrinsic magnetism and this is attributed to what is referred to as SPIN. For ANY electron, regardless of which orbital it is assigned to, there are two possible orientations for spin. ms = +1/2 (“spin up” or ) or ms = -1/2 (“spin down” or ) SCRIPT How many ways can the intrinsic magnetism of an electron in a 4d orbital be oriented? Two… three… five… or ten? PAUSE 2 SECONDS Any type of circular motion involving a charged particle,… such as the motion of an electron around the nucleus,… generates a magnetic field. CLICK In addition to the magnetism generated by the motion of an electron around the nucleus, experimental evidence suggest that electrons also have an intrinsic magnetism. This intrinsic magnetism is attributed to what is referred to as spin. CLICK For any electron, regardless of which orbital it is assigned to, there are two possible orientations for spin. We make a distinction between these two possible orientations using the spin quantum number ---- em sub ess. The two allowed values of em sub ess are Positive one half And negative one half The +1/2 case is known as the “spin up” case and an electron in this case is often symbolized by an upward pointing arrow. The –1/2 case is know as the “spin down” case and an electron in this case is often symbolized by a downward pointing arrow. The correct answer is 2. END RECORDING

Video ID: 2-3-7 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08