Unit 2: Electrons and Periodic Table

Hund's rule

"Empty seat rule" electrons are placed one at a time before pairing

s, p, and d orbitals contain how many total electrons?

18

Electron Configuration file order

1s2,2s2,2p6,3s2, 3p6,4s2,3d10,4p6 5s2,4d10,5p6,6s2 4f14,5d10,6p6,7s2 5f14,6d10,7p6

s orbital contains how many total electrons?

2

s, p, d, and f orbitals contains how many total electrons?

32

s and p orbitals contains how many total electrons?

8

group

A column on the periodic table

period

A horizontal row of elements in the periodic table

Henry Moseley

Arranged his periodic table by increasing atomic number

Atomic radii across a period?

Atomic radii decreases due to more coulumbic attraction

Dmitri Mendeleev

Credited with the first periodic table

valence electron

Electrons on the outermost energy level of an atom

Ionization energy down a group?

Ionization energy decreases due to less coulumbic attraction

Ionization energy across a period?

Ionization energy increases due to more coulumbic attraction

Noble Gases

No charge because of full valence shell; total of 18 noble gases

Valence electrons exist in what energy levels?

S and P sub levels

octet rule

States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons

Electron Shielding

a barrier made of inner electron shells which serves to decrease coulombic attraction and ultimately increases atomic radii

Continuous Energy

all amount of energy can be absorbed or released continuously, no specific quantities

ion

an atom or a bonded group of atoms that has a positive or negative charge

Excited state

any energy levels above the ground state

Line Emission Spectrum

categorizes element based on the emission given

Lewis structure

diagram of elements valence electrons, represented with dots. this is used to show an atom's ability to bond with other elements

Electronegativity down a group?

electronegativity decreases due to less coulombic attraction

Electronegativity across a period?

electronegativity increases due to more coulumbic attraction

Aufbau principle

electrons are added one at a time to the lowest energy level

Valence Electrons

electrons on most outer shell that helps with chemical bonds

Diatomic Elements

elements in nature that commonly bond with eachother; HOClBrIF (elements)

The Bohr model

explains how an electron jumps levels during excited states and ground state accompanied by absorption and emission of photons

Electromagnetic spectrum

form of energy (light) that exhibits wave-like behavior

noble gas

full valence shell, extremely unreactive

atomic radii down a group?

increases due to less coulumbic attraction

Ground State

lowest electron energy level in an atom

Pauli exclusion principle

max of 2 electrons can fit in each orbital. These electrons spin opposite directions

electron affinity trend

more electron affinity from left to right. More coulumbic attraction means more electron affinity. when element wants to get rid of electron, it has less electron affinity

Allotropes of elements

only one type of element bonded together

Mendeleev's periodic table

ordered by increasing atomic mass and consisted of basic properties, relative mass

electronegativity

the ability of an atom to attract electrons from another atom

Quantized Energy

the amount of energy absorbed or released can only be in specific quantities (cannot exist between energy levels)

Electron Affinity

the amount of energy released when an electron is added to a neutral atom to form a negative ion

ionization energy

the energy required to remove an electron from an atom

periodic law

the law that states that the repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements

Atomic Radii

the resulting radii of an atom from the nucleus to electron after coulombic attraction has been calculated. more coulombic attraction = less atomic radii