Periodic table Flashcards
Are groups vertical or horizontal?
Vertical
What do groups tell us?
The number of electrons in the outer shell
Are periods horizontal or vertical?
Horizontal
What does the period show us?
How many electron shells there are
What is the name for group 1?
Alkali metals
What is the name for group 2?
Alkali earth metals
What is the name for group 7?
Halogens
What group are the noble gases found in?
Group 8
What is the big chunk in-between group 2 and 3 called?
Transition metals
How was the first periodic table organised?
By octaves.
By mass, into patterns
New land
How did Mendeleev arrange the periodic table?
By mass
Left gaps
Arranged with similar patterns and could predict properties
Was correct
Properties of a noble gas
Full outer shell- don’t lose or gain electrons
Unreactive
Balloons and neon lights
8 electrons in outer except helium which has 2
Boiling point increase with increasing relative atomic mass (going down)
Properties of halogens
Non-metals Diatomic- Cl2 F2 Br2 Only gain 1 electron: form -1 ions, reduction Highly reactive Most reactive at the top Low boiling point at top, increases
React violently and rapidly with group 1 metals as they want to lose 1 electron
consist of molecules made of pairs of atoms
More reactive halogen can displace a less reactive halogen in an aqueous solution of its salt
Properties of Alkali metals
soft grey metals- kept in oil so no reaction with oil or water
Most reactive at the bottom because there is more shielding between the electron they want to use and positive nucleus
Low melting/ boiling point at the top
Want to lose electron
Properties of transition metals
Hard
shiny
good conductors
many have ions with different charge, form coloured compounds and are as useful as catalysts
