Periodicity (1) Flashcards
(14 cards)
What did dmitri Mendeleev discover in 1869?
That there were undiscovered elements
He left spaces for some unknown elements and arranged known ones so that similar ones were in columns
When the new elements were discovered they fit into the gaps and his predicted properties for them were correct
What elements have similar properties?
The ones in the same group- same electrons in their outer shells
What happens when a molecular substance melts?
The covalent bonds stay intact and the VDW break.
What’s the structure of phosphorus
P4
What’s the structure of sulfur?
S8
What does the melting temp of a substance equal?
Freezing temp
Where do you find elements that lose electrons when forming compounds?
Left
S block
Where do you find elements that accept electrons
Right
P block
What’s a characteristic of transition metals?
They have partly filled d orbitals- not full
So not all d block elements are transition metals
What is 1nm
1x10^-9
What happens to the atomic radii across the period
Decrease
What happens to the atomic radii down a group?
Increase
What happens to the 1st IE across a period
Increases
What happens to the 1st IE down a group?
Decreases
