The periodic table Flashcards
What happens to the atomic radius across a period?
Decreases
Why does the atomic radius decrease across a period?
The positive charge on the nucleus increases so the electrons are pulled closer to the nucleus, there is no more shielding
Why does sodium, magnesium and aluminium’s boiling points increase as you go across the period?
They are metals
They have an increasing positive charge
Increasing number of delocalised electrons
Decreasing radius
What type of structure does silicon have?
Macromolecular
Why does silicon have a high boiling point?
There are strong covalent links which take a lot of energy to overcome
Why are the boiling points of phosphorus, sulfur, chlorine and argon low?
They are simple molecular substances
They have van Der Waals which are weaker than the metallic bonding and covalent
Why is the boiling point of argon the lowest?
It is monatomic so there are very weak van Der waal forces
Why is there a general increase in ionisation energy as you go along period 3?
Increasing attraction between the outer shell electrons and the nucleus, due to the number of protons increasing
