Ms. Hoang’s ACP Chemistry Atomic Orbital Ms. Hoang’s ACP Chemistry

Concept Inventory True or False ______ According to current theory, electrons travel in concentric circles around the nucleus. ______ These concentric circles are called orbitals. ______ Orbitals are different from orbits. ______ The probability map of finding electron is called an orbital. ______ The energy level of each orbital is discrete and can be expressed in whole numbers n = 1, 2, 3, 4, 5,… ______ All orbitals are spherical shaped ______ One orbital can hold as many as 10 electrons

Wave Mechanical Model of the Atom Orbitals = electron cloud = probability map of finding electrons = easier to find electrons in the shaded regions The size of an atom is described as 90% probability of finding an electron at a given point in space

Hydrogen Energy Levels

Principal Energy Levels Electrons in an atom are contained in specific energy levels that are different distance from the nucleus Larger number = larger orbital (SIZE) Characterizes the energy of the electron in a particular orbital Designated by whole numbers and symbolized by n n = 1, 2, 3, 4, 5, 6,….. infinity

Sublevels Within each energy level is a volume of space where specific electrons are likely to be located. These spaces, called sublevels, are of different shapes The number of sublevels = n s orbitals: spherical p orbitals: like two balloons tied at the knots d orbitals: mainly like 4 balloons tied at the knot

The s orbital Each principal energy level has one s orbital Lowest energy orbital Spherical

The p orbitals Each principal energy level has three p orbitals 2nd lowest energy orbitals in principal energy level Two-lobed

The d orbitals Each principal energy level has five d orbitals 3nd lowest energy orbitals in principal energy level four-lobed

Summary

Pauli exclusion principle An atomic orbital can hold a maximum of two electrons, and those two electrons must have opposite spins

Concept Check-in True or False ______ According to current theory, electrons travel in concentric circles around the nucleus. ______ These concentric circles are called orbitals. ______ Orbitals are different from orbits. ______ The probability map of finding electron is called an orbital. ______ The energy level of each orbital is discrete and can be expressed in whole numbers n = 1, 2, 3, 4, 5,… ______ All orbitals are spherical shaped ______ One orbital can hold as many as 10 electrons