When more electrons are added to a single atom, the additional electrons tend to more evenly fill in a volume of space around the nucleus so that the resulting collection ( sometimes termed the atom ’ s “ electron cloud ” ) tends toward a generally spherical zone of probability describing where the atom ’ s electrons will be found.

When a core electron is removed, leaving a vacancy, an electron from a higher energy level may fall into the vacancy, resulting in a release of energy.

When an electron in an excited molecule or atom descends to a lower energy level, it emits a photon of light equal to the energy difference.

When it emerges from the specimen, the electron beam carries information about the structure of the specimen that is magnified by the objective lens system of the microscope.

When the electron beam interacts with the specimen, it loses energy by a variety of mechanisms.

When sodium ( Na ) and chlorine ( Cl ) are combined, the sodium atoms each lose an electron, forming cations ( Na < sup >+</ sup >), and the chlorine atoms each gain an electron to form anions ( Cl < sup >−</ sup >).

When an electron absorbs energy either from light ( photons ) or heat ( phonons ), it receives that incident quantum of energy.

When an electron is excited from a lower to a higher energy level, it will not stay that way forever.

When such an electron decays without external influence, emitting a photon, that is called " spontaneous emission ".

When a light-emitting diode is forward-biased ( switched on ), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons.

When an electron meets a hole, it falls into a lower energy level, and releases energy in the form of a photon.

When a chlorophyll molecule at the core of the photosystem II reaction center obtains sufficient excitation energy from the adjacent antenna pigments, an electron is transferred to the primary electron-acceptor molecule, pheophytin, through a process called photoinduced charge separation.

When a positron slows down to speeds similar to those of electrons in the material, the positron will annihilate an electron, releasing two gamma photons in the process.

When an X-ray photon collides with an atom, the atom may absorb the energy of the photon and boost an electron to a higher orbital level or if the photon is very energetic, it may knock an electron from the atom altogether, causing the atom to ionize.

When ionizing radiation strikes a semiconductor, it may excite an electron out of its energy level and consequently leave a hole.

When a small bias V is applied to the system, only electronic states very near the Fermi level, within eV ( a product of electron charge and voltage, not to be confused here with electronvolt unit ), are excited.

When the temperature and pressure in the core become sufficient to ignite helium fusion, a helium flash will occur if the core is largely supported by electron degeneracy pressure ( stars under 1. 4 solar mass ).

When the primary electron beam interacts with the sample, the electrons lose energy by repeated random scattering and absorption within a teardrop-shaped volume of the specimen known as the interaction volume, which extends from less than 100 nm to around 5 µm into the surface.

When an electron absorbs energy either from light ( photons ) or heat ( phonons ), it receives that incident quanta of energy.

When an electron is excited from a lower to a higher energy level, it will not stay that way forever.

When such an electron decays without external influence, emitting a photon, that is called " spontaneous emission ".

When an atom is probed by an external mechanism, such as a photon or a beam of electrons with energies in the range of 2 keV to 50 keV, a core state electron can be removed leaving behind a hole.

When the pressure applied on a parcel of air decreases, the air in the parcel is allowed to expand ; as the volume increases, the temperature falls and internal energy decreases.

When he returns home, Wallace ( Gibson ) falls in love with his childhood sweetheart, Murron MacClannough ( McCormack ), and they marry in secret so that she does not have to spend a night in the bed of the English lord.

When an object falls into a black hole, any information about the shape of the object or distribution of charge on it is evenly distributed along the horizon of the black hole, and is lost to outside observers.

When a particle falls into a black hole, it is boosted relative to an outside observer, and its gravitational field assumes a universal form.

When the key is released by the player, the far end returns to its rest position and the jack falls back.

When the player releases the key, the jack falls back down under its own weight, and the plectrum pivots backwards to allow it to pass the string.

* When the key is released, the jack falls back down under its own weight, and the plectrum passes back under the string.

A Viking longship is burnt during Edinburgh's annual Hogmanay celebrations ( though Edinburgh has no historical connection with the Norse invaders ). When Ne ' erday falls on a Sunday, 3 January becomes an additional public holiday in Scotland ; when Ne ' erday falls on a Saturday, both 3 and 4 January will be public holidays in Scotland ; when Ne ' erday falls on a Friday, 4 January becomes an additional public holiday in Scotland.

Rajiv Gandhi on a live TV show said of the carnage, " When a big tree falls, the earth shakes.

When discussing what complexity classes the integer factorization problem falls into, it's necessary to distinguish two slightly different versions of the problem:

Shortly before his resignation, he gave his final statement from 10 Downing Street, in which he said ; " When the curtain falls, it is time to get off the stage ".

When Odras falls asleep, the Morrígan turns her into a pool of water.

" When Mary meets Jesus, she falls at his feet.

Commenting on the anti-Sikh riots in the national capital Delhi, Rajiv Gandhi said, " When a giant tree falls, the earth below shakes "; a statement for which he was widely criticised.

When the count falls to zero, the file can be safely deallocated.

When Saul's other daughter Michal falls in love with David, Saul repeats the offer.

When the drop falls, it deposits the thinnest ring of calcite.

When his parents are out and the babysitter falls asleep, he dons his brother's Packers helmet and becomes Commander Keen, Defender of Earth.

When laser light which has been scattered off a rough surface falls on another surface, it forms an “ objective speckle pattern ”.

When the incoming voltage falls below a predetermined level the SPS turns on its internal DC-AC inverter circuitry, which is powered from an internal storage battery.

When the feast day of the patron saint of the parish church or monastery falls on a weekday of Great Lent, there is no Liturgy ( other than the Presanctified ), but fish is allowed at the meal.

When we consider 100 billion monkeys, the probability falls to 0. 17 %, and as the number of monkeys n increases, the value of X < sub > n </ sub > – the probability of the monkeys failing to reproduce the given text – approaches zero arbitrarily closely.