Chapter 5 Test Flashcards
Mendeleev’s role in creating the periodic table
Arranged the elements by increasing atomic mass and chemical/physical properties
What was the problem with how Mendeleev arranged the elements?
Some of the properties did not match up with the atomic masses
What was Mendeleevs solution to unknown elements when creating the table?
He left blank spaces where the elements should have been
What was Moseley’s role in creating the periodic table?
He rearranged the elements by increasing atomic number
Define the Periodic Law
The physical and chemical properties of the elements are periodic functions of their atomic numbers
Where are electrons added in a group?
sublevels in a higher energy level
Where are electrons added in a period?
the same energy level
Pattern of electron shielding in a group
increasing
Pattern of electron shielding in a period
remains the same
Pattern of force of attraction between protons and electrons in a group
decreases
Pattern of force of attraction between protons and electrons in a period
increases
What is electron shielding?
Inner shell electrons shield the outer electrons from nuclear attraction
What is group 1 called?
Alkali Metals
What is group 2 called?
Alkaline Earth Metals
Properties of Alkali Metals
very reactive, not found as free elements, silvery & soft
Properties of Alkaline Earth Metals
less reactive, not found as free elements, higher melting point
Which groups are the transition metals?
groups 3-12
How many valence electrons in group 1?
1
How many valence electrons in group 2?
2
Properties of transition metals
luster, solids, good conductors, less reactive
How many valence electrons in transition metals?
not predictable
What atomic numbers make up the Lanthanide Series?
atomic #58-71
What atomic numbers make up the Actinide Series?
atomic #90-103
Properties of the Lanthanide Series
shiny, less reactive
