3.1.3 BOONDINGDG

- They have very high melting and boiling points
- Soluble in polar solvents
- Dont conduct electricity when solid but can when molten or dissolved.

When one atom shares lone pair of electrons to form a bond

- Each pair of electrons in an atom will repel all other electrons pairs
- Pairs of electrons therefore will move as far apart as possible to minimise repulsion

the shape a molecule takes is based on the electron pairs repulsion

- If it has a positive charge, remove electron from least electronegative element and the opposite for if negative charge.

An atoms ability to pull a pair of electrons in a covalent bond

Same as ionisation

If the difference in electronegativity is less than 0.5

If the difference in electronegativity is equal to or greater than 2.5

If the difference in electronegativity is less than 2.5

If its electronegativity is equal to or less than 1.5

If its electronegativity is equal to or greater than 2.1

Hydrogen
Dipole dipole
Van der waal

forces of attraction that occur between opposite charged atoms in polar different molecules

N O F

It happeneds when hydrogen is covalently bonded to a NOF with a lone pair of electrons

Its when electrons in one molecule ends up on one side creating a temporary dipole which induces a temporary dipole on another molecule causing electrostatic attraction.

polar dissolves polar, nonpolar dissolves nonpolar

This is because the hydrogen bonds in ice holds the molecules further away resulting in large gaps. Called an open lattice structure which takes up more volume than liquid water would.

The partially positively charged hydrogen is attracted to the lone pair in negatively charged NOF in another molecule, forming an electrostatic attraction