Atomic and Molecular Structure

1. Atomic and Molecular Structure a. Students know how to relate the position of an element in the periodic table to its atomic number and atomic mass.
The Periodic Table organizes elements by their atomic number - from hydrogen (1) to whatever is the highest one currently known (>105). It is arranged so that similiar members fall in a list such as Chlorine Bromine etc.. The average atomic weight is usually shown with each element, but due to isotopes (caused buy nuclear varations) the weight is the normal average atomic weight. The table illustrates the similiarity of various elements such as metals, noble gases, rare earths, halides, etc. in that they fall into series within the table. The earliest periodic table was originated by Dimitri Mendeleif. b. Students know how to use the periodic table to identify metals, semimetals, non­ metals, and halogens.

c. Students know how to use the periodic table to identify alkali metals, alkaline earth metals and transition metals, trends in ionization energy, electronegativity, and the relative sizes of ions and atoms d. Students know how to use the periodic table to determine the number of electrons available for bonding.
I explain to my students that columns 4A-7A are 'wanna be' noble gases, ie want 8 valence e- (except for first period since only need 2 e-).
The elements are listed in columns and each of the A columns gives the number of valence electrons. Transition metals of course don't follow the same rules, so just talk about columns 1A-8A.
The atoms in columns 1A-4A can only make as many bonds as they have valence electrons, obviously.
I use molecule kits, but if you don't have them, use toothpicks and clay/playdough or have the kids make Bohr models on paper of one of the atoms in each column and they can see how many bonds can be formed.

e. Students know the nucleus of the atom is much smaller than the atom yet contains most of its mass.
An atomic nucleus is much, much smaller than an atom. The cloud of electrons that "orbit" the nucleus and define the "size" of an atom is roughly 100,000 times as large as that atom's nucleus! For example, a helium atom has a size of about 1 Ångström (0.1 nanometers or 10-10 meters), while its nucleus is only 1 femtometer (10-15 meters) in diameter. If you made a scale model of an atom with a nucleus the size of a pea, the electrons would zing around in a space larger than a major sports stadium! An atom is mostly empty space.

The number of protons in the nucleus determines what type of element the atom is. The number of protons is called the element's "atomic number". For example, hydrogen has an atomic number of one, since all hydrogen atoms have one proton in their nucleus. Carbon has 6 protons, so its atomic number is 6; oxygen has 8 protons, so its atomic number is 8. Uranium has 92 protons, so its atomic number is 92! If we count the number of protons plus neutrons, we get an atom's atomic mass. Most elements come in different versions, called "isotopes", with different numbers of neutrons. For example, the most common form of carbon is carbon-12 (12C); that isotope of carbon has 6 protons and 6 neutrons, and thus an atomic mass of twelve. Another isotope of carbon, carbon-14 (12C), has 6 protons and 8 neutrons, hence and atomic mass of fourteen. 12C is radioactive and is used to determine how old things are in a technique called "carbon dating".

f. Students know how to use the periodic table to identify the lanthanide, actinide, and transactinide elements and know that the transuranium elements were synthesized and identified in laboratory experiments through the use of nuclear accelerators. An electrostatic nuclear accelerator is one of the two main types of particle accelerators, where charged particles can be accelerated by subjection to a static high voltage potential. The static high voltage method is contrasted with the dynamic fields used in oscillating field particle accelerators. Owing to their simpler design, historically these accelerators were developed earlier. These machines are operated at lower energy than some larger oscillating field accelerators, and to the extent that the energy regime scales with the cost of these machines, in broad terms these machines are less expensive than higher energy machines, and as such they are much more common. Many universities world wide have electrostatic accelerators for research purposes.

g. Students know how to relate the position of an element in the periodic table to its quantum electron configuration and to its reactivity with other elements in the table. All elements withing the same group (Alkali metals for example) will have an electron configuration that ends the same way (s1 for alkali metals, s2 for Alkaline earth, Groups 3-8 end in p1, p2, p3, p4... so on. The trasition metals end with d orbitals of an energy level one less than the period the element is found in. Lanthanides and actinides end in f orbitals with an energy level equal to its period # minus 2.)

h. Students know the experimental basis for Thomson’s discovery of the electron,
Rutherford’s nuclear atom, Millikan’s oil drop experiment, and Einstein’s expla­ nation of the photoelectric effect.
When a surface is exposed to sufficiently energetic electromagnetic energy, light will be absorbed and electrons will be emitted. The threshold frequency is different for different materials. It is visible light for alkali metals, near-ultraviolet light for other metals, and extreme-ultraviolet radiation for nonmetals. The photoelectric effect occurs with photons having energies from a few electronvolts to over 1 MeV. At the high photon energies comparable to the electron rest energy of 511 keV, Compton scattering may occur pair production may take place at energies over 1.022 MeV.

i. * Students know the experimental basis for the development of the quantum theory of atomic structure and the historical importance of the Bohr model of the atom.

quantum mechanics, in physics, a theory based on using the concept of the quantum unit to describe the dynamic properties of subatomic particles and the interactions of matter and radiation. The foundation was laid by the German physicist Max Planck, who postulated in 1900 that energy can be emitted or absorbed by matter only in small, discrete units called quanta. Also fundamental to the development of quantum mechanics was the uncertainty principle, formulated by the German physicist Werner Heisenberg in 1927, which states that the position and momentum of a subatomic particle cannot be specified simultaneously.

j. * Students know that spectral lines are the result of transitions of electrons between energy levels and that these lines correspond to photons with a frequency related to the energy spacing between levels by using Planck’s relationship (E�=� hv)