Chapter 6 Flashcards
What is the photoelectric effect?
Each metal has a different energy at which it ejects electrons. At lower energy, electrons are not emitted.
What is the formula for photoelectric effect?
E = hf - φ
What are quantum mechanics?
A mathematical treatment into which both the wave and particle nature of matter could be incorporated.
What does the solution of Schrödinger’s wave equation for hydrogen yield?
The solution of Schrödinger’s wave equation for hydrogen yields wave functions for the electron.
What is electron density?
Probability of where an electron is likely to be at any given time.
What does solving the wave equation give?
Solving the wave equation gives a set of wave functions, or orbitals, and their corresponding energies.
What does each orbital describe?
Each orbital describes a spatial distribution of electron density.
How are orbitals described?
An orbital is described by a set of three quantum numbers.
What does the principal quantum number describe?
The principal quantum number, n, describes the energy level on which the orbital resides.
What are the properties for s orbitals?
The value of l for s orbitals is 0, they are spherical in shape, and the radius of the sphere increases with the value of n.
What are the properties for p orbitals?
The value of l for p orbitals is 1, and they have two lobes with a node between them.
What are the properties for d orbitals?
The value of l for a d orbital is 2, and four of the five d orbitals have four lobes; the other resembles a p orbital with a doughnut around the center.
What are the properties for f orbitals?
Very complicated shapes (not shown in text,) seven equivalent orbitals in a sublevel, and l = 3.
What is spin quantum number?
The “spin” of an electron describes its magnetic field, which affects its energy.
What is the Pauli Exclusion Principle?
No two electrons in the same atom can have the same set of four quantum numbers. Therefore, no two electrons in the same atom can have the exact same energy. This means that every electron in an atom must differ by at least one of the four quantum number values: n, l, ml, ms.
What is electron configuration?
The way electrons are distributed in an atom is called its electron configuration.
What is ground state?
The most stable organization is the lowest possible energy, called the ground state.
What does each component consist of?
A number denoting the energy level;
a letter denoting the type of orbital;
a superscript denoting the number of electrons in those orbitals.
What is an orbital diagram?
Each box in the diagram represents one orbital. Half-arrows represent the electrons. The direction of the arrow represents the relative spin of the electron.
What is Hund’s rule?
This means that, for a set of orbitals in the same sublevel, there must be one electron in each orbital before pairing and the electrons have the same spin, as much as possible.
What are condensed electron configurations?
We write a shortened version of an electron configuration using brackets around a noble gas symbol and listing only valence electrons.
What’s special about transition metals electron configuration?
Transition metals follow the filling of 4s by filling 3d in the 4th period.
