2.2 Periodic Table Flashcards
Who’s the father of the periodic table?
Dmitri Mendeleev
Describe the first system of organizing the 62 known elements.
within rows and columns based on increasing mass and similar chemical and physical properties
Define Element
– substance that cannot ordinarily be broken down into similar substances
– not destroyed by acids
– not changed by electricity, light, heat
Elements have both __ and __ properties
– physical
– chemical
How does the arrangement of the modern Periodic Table differ as opposed to earlier?
arranged according to atomic #, not atomic mass
Name the three subdivisions of elements on the Periodic Table + their properties
- Representative elements: both metals and nonmetals
- Transition elements: metals
- Lanthanides and Actinides
Name the groups + locations within the Representative elements subdivision
– Group 1: Alkali Metals
– Group 2: Alkaline Earth Metals
– Group 17: Halogens
– Group 18: Noble Gases
What are rows on the periodic table called
periods
What are columns on the periodic table called
groups/families
the elements in each group have similar __ properties
physical/chemical
list some defining characteristics of Metals
– malleable
– ductile
– lustrous
– conductive
– positive electric charge
list some defining characteristics of nonmetals
– usually brittle
– dull
– non-conductive
– negative charges or neutral
Why does Hydrogen appear in both Group 1 and 17?
under certain circumstances can behave as if metallic or non-metallic
what is the atomic #
whole # equal to the # of protons in the element’s atom
define atomic mass
avg mass of an element’s atom compared to an atom of carbon-12