C5: The Periodic Table Flashcards
Alkali Metals
> Group 1
Very reactive, have to be stored in oil.
Low density
Very soft, can be cut with a knife
Silvery, shiny until they react with the oxygen in the air.
Low melting/boiling points.
Reaction with water produces a metal hydroxide.
All soluble in water. Produce a colourless solution with an alkaline pH.
More reactive down the group.
The Transition Elements
> Good conductors
Hard and Strong
High Density
High Melting and Boiling Points (except Mercury)
Not v. reactive.
Often used as catalysts
Charge often given in the name (Iron (II))
The Halogens
> Group 7 > Poisonous non-metals > Low melting and boiling points > Poor conductors > Reactivity decreases down the group > More reactive Halogens displace less reactive ones.
What is harder for large atoms?
gaining extra electrons
What is easier for large atoms?
losing electrons
Why do the Alkali Metals get more reactive going down?
Because the atoms get bigger, and the outer shell is further away from the nucleus.
This means the electrostatic attraction is weaker.
The other, inner shells, also shield the outer shell from the electrostatic attraction.
This means that it is easier for the outer electron to be removed.
Why do the Halogens get less reactive going down?
Because of the shielding of the inner shells and lack of electrostatic attraction to the outer shell, it is harder for the bigger atoms to attract electrons.