PT trends Flashcards
PERIOD
horizontal row
GROUP
vertical column
PERIODIC LAW:
The properties of the chemical elements recur periodically when the elements are arranged from lowest to highest atomic numbers
Alkali Metals:
elements in the 1st column (except H)
Alkaline Earth Metals:
elements in the 2nd
column
Halogens:
elements in the column headed by Flourine
Noble Gases:
elements in the column headed by He
Lanthanides:
elements in the row starting with
Lanthanium
Actinides:
elements in the row starting with actinum
The Properties of Metals:
• Reflect light when polished
• Are opaque
• Good conductors of electricity and heat
• Are generally flexible when in thin sheets
• Are generally malleable (can be hammered into thin
sheets) and ductile (drawn or stretched into wires)
• Usually solid at room temp
The Properties of Non‐metals:
• Are gases, liquids or brittle solids at room temperature
• Are poor heat and electrical conductors
• If solids, are dull to lustrous in appearance and opque to
translucent
The Properties of Metalloids:
• They have properties which resemble metals more
than non‐metals
The important difference between metals and
metalloids:
• Metals: Electrical conductivity DECREASES
with INCREASING temperature
• Metalloids: Electrical conductivity
INCREASES with INCREASING temperature
Metallic Properties: Left to right across the table & reason
• Left to right across the table ‡ metallic properties
decrease
‐ Reason: Moving from the metal side to the non‐metal
side of the PT
Metallic Properties: Down a family
• Down a family ‡ metallic properties increase