Periods 2 & 3 Flashcards
What is ionisation energy?
The minimum amount of energy required to remove the most loosely bound electron.
Why does ionisation energy increase across periods 2 &3?
- The electrostatic attraction increase
- The amount of protons increase.
- The electrons are held more tightly
- Shielding levels stay approximately the same as the electrons on each element are on the same shell.
Why is there an exception to ionisation energy in B/Al and O/S?
It starts a new orbital which means that it is at a higher energy level so it’s easier to remove.
Why is there an exception to ionisation energy in N/O?
The electrons repel against each other making the first electron easier to remove?
What happens to ionisation energy as you go across the periods 2&3?
It increases.
Why does atomic radii decrease as you go across the periods?
- There is the same outer shell of electrons in each element.
- The proton number increases.
- There is a higher atomic charge which pulls the outer electrons closer.
What happens to atomic radii as you go across periods?
It decreases.
What is periodicity?
Trends in the periodic table.
What is the melting point in Li, Be, B, Na, Mg & Al?
A high melting point.
Why do Li, Be, B, Na, Mg & Al have high melting points?
They are giant metallic structures which require more energy to break the bonds.
What is melting point & boiling point associated with?
Intermolecular forces
What is the melting point in Si & C?
A very high melting point.
Why do Si & C have very high melting points?
Giant covalent lattice which require large amount of energy to break the bonds.
As you go across the period what happens to the metallic bonds?
There is a stronger metallic charge due to an increasing charge.
What are N, O, F, Ne, P, S, Cl & Ar?
Simple London forces.
