Filling order

Relative energies, so far as filling order is concerned, for the molecular orbitals formed by combining 2s and 2p atomic orbitals. 

The discrepancy between the two sequences of numbers representing the closing of shells and the closing of periods occurs, as is well known, due to the fact that the shells are not sequentially filled. Instead, the sequence of filling follows the so-called Madelung rule, whereby the lowest sum of the first two quantum numbers, n + 1, is preferentially occupied. As the eminent quantum chemist Lowdin (among others) has pointed out, this filling order has never been derived from quantum mechanics (2),... 

The arrangement of the periodic table provides a simple way to determine the filling order of the elements, as shown in Figure 8-f0 and applied in Example. ... 

For most atomic ions, the filling order of orbitals is the same as that of neutral atoms. For example, Na, Ne, and F all contain 10 electrons, and each has the configuration. Atoms and ions that have the same... 

A neutral chromium atom has 24 electrons, so the corresponding Cr cation has 21 electrons. The first 18 electrons follow the usual filling order to give the argon core configuration ... 

The d electron count is correct (8), and the filling order follows both the Pauli principle and Hund s rule. 

In writing the electronic configuration of an atom, make sure you use the correct filling order. 

In the process of examining the patterns outlined below, you will learn the filling order for atoms of elements in periods 5, 6, and 7. You will also see why the shape and organization of the periodic table is a direct consequence of the electronic structure of the atoms. 

Elements that appear in the d block are called the transition elements. They mark the transition from the p orbital filling order to the d orbital filling order. By the same reasoning, the /block elements are called the inner transition elements, because they mark a transition from the d orbital filling order to the / orbital filling order. 

Reading the periodic table from left to right, starting at the top and finishing at the bottom, displays tbe filling order and the energy order of the atomic orbitals. 

In the heavier transition series elements, especially the lanthanides and actinides, there are numerous exceptions to the regular filling order predicted by the building-up principle. Suggest an explanation for why more exceptions would be noted for these elements. 

It was reported by the Institute for Safe Medication Practices (ISMP) in 2000 that fewer than 5 percent of physicians were writing prescriptions electronically. In a 2000 white paper entitled, A Call to Action Eliminate Handwritten Prescriptions within 3 Years, ISMP recommended the use of electronic prescribing by clinician order entry to reduce medication errors (ISMP, 2000). CPOE can help to reduce errors in the delivery and transcribing of orders to the pharmacy where the orders are filled. Order management can be used to control inventory and alert pharmacy staff (and even the patient) of the status of a prescription. For example, some national chain pharmacies have the capability of alerting the patient by phone or e-mail if a prescription is ready or if other action needs to be taken before the prescription can be picked up. The system should also be able to report results, such as the number of prescriptions filled, the revenue generated over a specified time, and medication error reports. 

A label and/or a medication profile is printed. A copy of the original prescription or medication order continues to accompany the label or medication profile while the order is filled. Orders never should be filled solely on the basis of what appears on the label or medication profile because the computer entry may have been in error. 

Fill order p p Pz then p PyPt providing For the filled orbitals p P Pz1... 

According to Hund s rule, the electrons fill their orbitals singly and then they begin to pair up. This means that the second situation shown above is the correct filling order for the electrons. 

Figure 1.1 Filling Order and Relative Energy Levels of Orbitals 1.1.3 Atomic Orbitals...

A useful way to remember the filling order for electrons in atoms. 

Figure 8.7 Aid to memorizing sublevel filling order. List the sublevels as shown, and read from 1s, following the direction of the arrows. Note that the...

Understand orbital filling order, how outer configuration correlates with chemical behavior, and the distinction among inner, outer, and valence electrons write the set of quantum numbers for any electron in an atom as well as full and condensed electron... 

Perhaps the easiest way to determine the correct filling order is to use the periodic table. (See Figure 4). The square for each element represents the most recendy added electron. In the first shell there are two s electrons in the second there are two s and six p electrons and in the third there are two r and six p electrons, and then ten more fill up the 3d orbitals after the fourth shell has begun. The transition elements result from electrons filling in the d orbitals, and the lanthanide and actinide elements from electrons filling in the/orbitals. 

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