ARMRIT STUDY GUIDE PACKET GRADED A+

ATOMS - FUNDAMENTAL SUBMICROSCOPIC UNIT OF ALL MASS. SIZE OF THE ATOM AND ITS WEIGHT HAVE INTERESTED SCIENTISTS FOR A LONG PERIOD. SUBSEQUENTLY, EXPERIMENTS WERE DEVISED TO DETERMINE THE SIZE AND WEIGHT OF THE VARIOUS ATOMS. THE LIGHTEST OF ALL ATOMS IS HYDROGEN. PROTON - A SUBATOMIC PARTICLE HAVING A POSITVIE CHARGE IDENTICAL IN MAGNITUDE TO THE NEGATIVE CHARGE OF AN ELECTRON AND, TOGETHER WITH THE NEUTRON, A COMPONENT OF ALL ATOMIC NUCLEI. THE PROTON FORMS, BY ITSLEF, THE NUCLEUS OF THE HYDROGEN ATOM. THE MASS OF A PROTON IS APPROXIMATELY 1836 TIMES THAT OF AN ELECTRON AND THE MASS OF AN ATOM IS CONTAINED ALMOST ENTIRELY IN THE NUCLEUS. THE PROTON HAS AN INTRINSIC ANGULAR MOMENTUM OR SPIN AND THUS A MAGNETIC MOMENT (VERY SMALL MAGNETIC FIELD). THE NUMBER OF PROTONS IN THE NUCLEUS OF AN ATOM DETERMINES WHAT ELEMENT IT IS; THE ATOMIC NUMBER OF AN ELEMENT DENOTES THE NUMBER OF PROTONS IN THE NUCLEUS. ELECTRON - A SUBATOMIC MPARTICLE THAT, ALONG WITH PROTONS AND NEUTRONS, MAKE UP THE ATOMS THE FLOW OF AN ELECTRIC CURRENT IN A CONDUCTOR IS CAUSED BY THE DRIFTING OF FREE ELECTRONS IN THE CONDUCTOR. HEAT CONDUCTION IS ALSO PRIMARILY A PHENOMENON OF ELECTRON ACTIVITY. THE CHARGE OF THE ELECTRON IS THE BASIC UNIT OF ELECTRICITY. ELECTRONS HAVE HALF-INTEGRAL SPIN; SPIN IS A PROPERTY OF SUBATOMIC PARTICLES THAT INDICATES THE PARTICLE'S ANGULAR MOMENTUM. NEUTRON - A SUBATOMIC PARTICLE THAT IS NEUTRAL THEREFORE HAS NO CHARGE. IT IS LOCATED IN THE NUCLEUS AND SERVES AS A STABILIZER. THE MASS OF A NEUTRON IS SLIGHTLY GREATER THAN THE PROTON MASS AND HAS AN ENORMOUS EFFECT ON THE QUANTUM SPIN VALUE OF AN ELEMENT. THE NET CHARGE ON A NEUTRON IS 0 MAGNETISM - IS DESCRIED AS THE ABILITY OF A SUBSTANCE TO ATTRACT IRON, COBALT AND NICKEL. IT IS THE POWER OR FORCE CREATED BY A SUBSTANCE HAVING THE PROPERTY OF CREATING OR INDUCING MAGNETIC DIPOLES. THE MAGNETIC FIELD OF ANY MAGNET HAS A DIRECTION, SIGNIFIED NORTH AND SOUTH. THIS PROPERTY OF A MAGNET MAKES IT A DIPOLE. DIPOLE - A MAGNETIC FIELD CHARACTERIZED BY ITS OWN MAGNETIC NORTH AND SOUTH POLES SEPARATED BY A FINITE DISTANCE. MAGNETIC SUSCEPTIBILITY - DEFINED AS THE TENDENCY OF A SUBSTANCE TO ATTRACT OR REPEL MAGNETIC LINES OF FORCE DEPENDENT ON THE MAGNETIC PROPERTIES OF ITS ELECTRONS.DIAMAGNETIC - THE PROPERTY OF MOST SUBSTANCES WITH PAIRED ORBITAL ELECTRONS THAT HAVE OPPOSITE SPINNING AND THEIR MAGNETIC MOENTS CANCEL EACH OTHER OUT. SUBSTANCES WITH DIAMAGNETIC SUSCEPTIBILITY WEAKLY ATTRACT OR REPEL MAGNETIC LINES OF FORCE. MAGNETIC SUSCEPTIBILITY OF MOST HUMAN BODY TISSUES ARE DESCRIBED AS DIAMAGNETIC. PARAMAGNETIC - THE PROPERTY OF SUBSTANCES WITH POSITIVE MAGNETIC SUSCEPTIBILITY THAT ATTRACT AND REPEL MAGNETIC LINES OF FORCE. THESE SUBSTANCES (GADOLINIUM, METHEMOGLOBIN, FREE RADICALS) CONTAIN ONE OR MORE UNPAIRED ORBITAL ELECTRONS AND PRODUCE MARKED REDUCTIONS IN THE T1 AND T2 RELAXATION TIMES. UNPAIRED ORBITAL ELECTRONS SPIN IN THE SAME DIRECTION AND HAVE THE TENDENCY TO LINE UP WITH THE MAGNETIC FIELD. THEREFORE PRODUCING ADDITIONAL MAGNETIC FIELDS. SUPER-PARAMAGNETIC - THE PROPERTY OF SUBSTANCES WITH LARGE POSITIVE MAGNETIC SUSCEPTIBILITY WHICH STRONGLY ATTRACT OR REPEL MAGNETIC LINE SOF FORCE. THESE SUBSTANCES (HEMOSIDERIN AND SUPERPARAMAGNETIC IRON OXIDE -SPIO) HAVE A SINGLE MAGNETIC DOMAIN AND ARE MAGNETIZED IN A MAGNETIC FIELD. THEIR MAGNETIC SUSCEPTIBILITIES ARE MUCH LARGER THAN THOSE OF PARAMAGNETIC SUBSTANCES AND SIMILAR TO THOSE OF FERROMAGNETIC MATERIALS. UNLIKE FERROMAGNETIC SUBSTANCES, SUPERPARAMAGNETIC MATERIALS DO NOT EXHIBIT RESIDUAL MAGNETISM WHEN THE EXTERNAL FIELD IS REMOVED.