Unit 4 Flashcards
Schrödinger
An Austrian physicist who disagreed with the Bohr Model and determined the probability of finding electrons around the nucleus.
What is the Quantum Model (Electron Cloud Model)
A model that shows that electrons are restricted to different energy levels and that electrons don’t orbit the nucleus in a set path, but in a floating motion.
Where are electrons located
The location is described by the probability of finding an electron in a specific area. These areas re 3-D and are called orbitals (electron clouds)
Energy levels
Describe the distance of the orbitals from the nucleus. Is equal to 1,2,3,4 with 1 being the closest to the nucleus.
Sublevel
Describes the shape of the orbital. The number of different sub levels equals the value for the energy level.
S=2e- and 1 energy level, P=6e- and 2 energy levels, D=10e- and 3 energy levels, and F=14e- and 4-7 energy levels.
Electron Configuration
A way to communicate the location of electrons in an atom.
How to write an electron configuration
1: Determine the number of electrons from the periodic table.
2: Follow the Aufbau Principle, which states that an electron will occupy the lowest energy orbital first. Energy level-electron fill 1, 2, 3, 4 (except for D and F orbitals). Sublevel-electrons fill S, P, D, and F.
Noble Gas shortcut
Noble gases are located in the last column on the periodic table. Pick the closest noble gas that comes before that element, then continue the electron configuration.
Mendeleev
A Russian chemist and inventor who arranged the elements in order of increasing atomic mass. He noticed that similarities in their chemical properties appeared at regular intervals.
Problems with Mendeleev’s periodic table
Based on properties, some elements did not go in order of atomic mass. There seemed to be empty spots, where he predicted the existence and properties of undiscovered elements.
Moseley
An English physicist that realized that elements could be arranged by increasing atomic number instead. This solved the mass problem and is the method used today.
Metals
Left of the staircase Usually solid High melting point Shiny Malleable Good conductor of heat and electricity Ready to lose electrons
Nonmetals
Right of the staircase Usually gas Low melting point Dull Poor conductor of heat and electricity Ready to gain electrons
Metalloids
Touching the staircase Always solids Moderate melting points Shiny or dull Maleable Okay conductor of heat and electricity Lose/gains electrons
Alkali metals
Group 1 (except H)
1 valence electron
Very high reactivity
Soft metals
