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1/18/18

Wave Mechanical Model of

— have a series of levels Configuration called principal energy levels Pictures — These are designated by whole numbers (symbolized by n) — n can equal 1 , 2, 3, 4…. Mrs. Dormer Organic — Level 1 corresponds to n = 1, level 2 corresponds to n = 2 and so on.

— Each principal energy level contains one or more —The energy of the level types of orbitals called sublevels. increases as the value of n — Sublevels are identified by letters – increases. s, p, d, f

— The number of sublevels present in a given principal energy level equals n. — For example, level 1 contains one sublevel — The 1s orbital

— Level 2 contains two sublevels (two types of orbitals) — The 2s orbital and three 2p orbitals

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— The n value is always used to level the orbitals of a given principal level and is followed by a letter that indicates the type (shape) of the orbital.

— For example, the designation 3p means an orbital in level 3 that has two lobes (a p orbital always has two lobes).

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—An orbital can be empty or it —The shape of an orbital does not can contain one or two indicate the details of electron , but never more than movement. It indicates the two. If two electrons occupy the probability distribution for an same orbital, they must have electron residing in that orbital. opposite spins.

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The Wave Mechanical Model The Wave Mechanical Model of the Atom of the Atom

1. Atoms have a series of energy levels 2. The energy of the level increases as the called principal energy levels which value of n increases. are designated by whole numbers symbolized by n. Level 1 corresponds to n = 1, level 2 corresponds to n = 2, 3. Each principal energy level contains and so on. one or more types of orbitals called sublevels.

The Wave Mechanical Model The Wave Mechanical Model of the Atom of the Atom

4. The number of sublevels present in a

given principal energy level equals n. n Sublevels (Types of Orbitals) Present For example, level 1 contains one 1 1s (1) sublevel (1s); level 2 contains two 2 2s (1) 2p (3) sublevels, the 2s orbital and the three 3 3s (1) 3p (3) 3d (5) 2p orbitals. 4 4s (1) 4p (3) 4d (5) 4f (7)

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The Wave Mechanical Model The Wave Mechanical Model of the Atom of the Atom

5. The n value is always used to label the 6. An orbital can be empty or it can contain orbitals of a given principal level and one or two electrons, but never more than two. If two electrons occupy the same is followed by a letter that indicates orbital, they must have opposite spins. the type (shape) of the orbital. For example, the designation 3p means an orbital in level 3 that has two lobes. 7. The shape of an orbital does not indicate the details of electron movement. It indicates the probability distribution for an electron residing in that orbital.

Practice Examples – T or F

1) An s orbital is always spherical in shape.

True. The size of the sphere increases as n increases, but the shape is always spherical.

Practice Examples – T or F

2) The 2s orbital is the same size as the 3s orbital.

False. The 3s orbital is larger (the electron is farther from the nucleus on average) than the 2s orbital.

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Practice Examples – T or F

3) The number of lobes on a p orbital increases as n increases. That is, a 3p orbital has more lobes than a 2p orbital.

False. A p orbital always has two lobes.

Practice Examples – T or F Practice Examples – T or F

4) Level 1 has one s orbital, level 2 5) The electron path is indicated by has two s orbitals, level 3 has three the surface of the orbital. s orbitals, and so on.

False. Each principal energy level False. The electron is somewhere inside the orbital surface 90% of the time. The has only one s orbital. electron does not move around on this surface.

Practice Examples – T or F Practice Examples – T or F

6) The shape of a given type of 7) The number of types of orbitals in orbital changes as n increases. a given energy level is the same as the value of n.

False. The shape of a given orbital True. For example, in n = 2 there are stays the same while the size two types of orbitals (s and p). increases.

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Practice Examples – T or F

8) The atom has a 3s orbital.

True. There are no electrons in the 3s orbital for a in its lowest energy state, but the orbital is a potential space, not a physical structure.

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