Chemistry Periodic Trends Quiz

Electron Affinity

The energy change occurring when an anion of the element in the gaseous phase loses an electron

Across a Period: Electron Affinity

Increases. Why? Greater Positive Nuclear Charge

Down a Group: Electron Affinity

Decreases. Why? 1) Increased number of energy levels 2) Increased electron repulsion

Ionization Energy

The energy required to remove an electron from an atom

Across a Period: Ionization Energy

Increases. Why? Greater Positive Nuclear Charge

Down a Group: Ionization Energy

Decreases. Why? 1) Increased number of energy levels 2) Increased electron repulsion

Moseley

Revised periodic table and arranged elements according to Atomic Number

Mendelev

Proposed 1st periodic table where elements were arranged according to Atomic Mass

Chemical Reactivity - Families

Similar valence electrons in a group result in similar chemical properties

Electronegativity

The tendency for an atom to attract electrons to itself when it is chemically combined with another element

Across a Period: Electronegativity

Increases. Why? Greater Positive Nuclear Charge

Down a Group: Electronegativity

Decreases. Why? 1) Increased number of energy levels 2) Increased electron repulsion

Across a Period: Atomic Radius

Decreases. Why? Greater Positive Nuclear Charge

Down a Group: Atomic Radius

Increases. Why? 1) Increased number of energy levels 2) Increased electron repulsion

Group 1

Alkali Metals

Group 2

Alkaline Earth Metals

Group 3

Transition Metals

Group 4

Halogens

Group 5

Noble Gases

Group 6

Metalloids

Ionic Radius: Cations

Positive charge, lost electrons, gets smaller

Ionic Radius: Anions

Negative charge, gained electrons, gets bigger

Melting/Boiling Point

Highest in the middle of a period