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Approximate probability distribution of the 1s orbital shown with axes to emphasize the 3-dimensional spherical shape.

For now, the only other shape we will worry about corresponds to l = 1. In this case, the orbital is not spherical at all. Instead, it consists of two clouds or “lobes” on opposite sides of the nucleus, as in [link] . This type of orbital is given the one letter name “p,” which actually stands for “principal.” Looking at the p orbitals in [link] , it is reasonable to ask what direction the two lobes are pointing in. If it seems that the lobes could point in any of three directions, that is correct. There are three “p” orbitals for each value of n , each one pointed along a different axis, x, y, or z. The third quantum number m gives each orbital a name allowing us to distinguish between the three orbitals pointing perpendicularly to each other. In general, the m quantum number must be an integer between –l and +l . When l = 1, m can be -1, 0 or 1. This is why there are three p orbitals.

Approximate probability distributions of p orbitals shown along the x, y, and z axes.

Although we will not worry about the shape of the l = 2 orbitals for now, there are two things to know about them. First, these orbitals are given the single letter name d . Second there are five d orbitals for each n value, since l = 2 and therefore m can be -2, -1, 0, 1, or 2.

Chemists describe each unique orbital with a name which tells us the n and l quantum numbers. For example, if n = 2 and l = 0, we call this a 2s orbital. If n = 2 and l = 1, we call this a 2p orbital. Remember though that there are three 2p orbitals since there are three m values (-1, 0, 1) possible.

The motion of an electron in a hydrogen atom is then easily described by telling the quantum numbers or name associated with the orbital it is in. In our studies, an electron can only be in one orbital at a time, but there are many orbitals it might be in. If we refer to a 2p electron, we mean that the electron is in an orbital described by the quantum numbers n = 2 and l = 1. The n = 2 value tells us how large the orbital is, and the l = 1 value tells us the shape of the orbital. Knowing the orbital the electron is in is for now everything that we can know about the motion of the electron around the nucleus.

Observation 3: photoelectron spectra and electron configurations

So far, we have been concerned almost entirely with describing the motion of the electron in a hydrogen atom. Fortunately, this will be helpful in understanding the motion of electrons in all other atoms. The most important differences between the hydrogen atom and all other atoms are the charge on the nucleus, the number of electrons, and the effects of the repulsions of the electrons from each other. Electron-electron repulsion is not important in a hydrogen atom since it contains only a single electron, but it is very important in all other atoms.

To begin to understand the energies and orbitals for electrons in other atoms, we need more experimental information. We look at a new experiment called photoelectron spectroscopy. This form of spectroscopy is similar to the photoelectric effect we discussed in the previous concept study. We shine light on an atom and measure the minimum frequency of light which will ionize an electron from an atom. Remember that the frequency of light corresponds to a specific energy of the photons in that light. When the frequency of light is too low, the photons in that light do not have enough energy to ionize electrons from an atom. As we increase the frequency of the light, we find the minimum frequency, or threshold, at which electrons begin to ionize. As we continue to increase the frequency, we find that additional electrons are ionized at higher thresholds. These electrons are more tightly bound to the atom, requiring more energy and thus a greater frequency of light to ionize. By finding these higher thresholds for ionization, we can measure the ionization energy of not only the outermost electron but also of each electron in each orbital. With a higher frequency of light, there is sufficient energy to ionize a number of different electrons, each with its own energy. The different types of electrons are distinguishable from each other by their kinetic energies when they are ionized. The more energy which is required to ionize the electron, the less energy is left over for the kinetic energy of the ionized electron. This means that we can look at the energies of all of the electrons in an atom, not just the electrons with the highest energy.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Concept development studies in chemistry 2012. OpenStax CNX. Aug 16, 2012 Download for free at http://legacy.cnx.org/content/col11444/1.4
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