Absolute zero. Zero kelvin (â273.15 Â°C) is defined as absolute zero. Absolute zero is the lower limit of the thermodynamic temperature scale, a state at which the enthalpy and entropy of a cooled ideal gas reaches its minimum value, taken as 0. Absolute zero is the point at which the fundamental particles of nature have minimal vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion. The theoretical temperature is determined by extrapolating the ideal gas law; by international agreement, absolute zero is taken as ...
The nuclear spins for individual protons and neutrons parallels the treatment of electron spin, with spin 1/2 and an associated magnetic moment. The magnetic moment is much smaller than that of the electron. For the combination neutrons and protons into nuclei, the situation is more complicated.
In the center of every atom is a tiny, dense nucleus. The nucleus contains two kinds of particles: neutrons, which have no charge, and positively charged protons. These orbitals surrounding the nucleus have different levels of energy - the farther away each is from the nucleus, the more energy it has.