4.2.1 - Trends in group 7 Flashcards
What is the appearance of fluorine?
A yellow gas
What is the appearance of chlorine?
A green gas
What is the appearance of bromine?
A brown liquid
What is the appearance of Iodine?
Purple/black solid
What happens to the size of molecules and reactivity as you descend group 7?
Size of molecules increases
Reactivity decreases
How is a temporary dipole induced?
Electron movements
Are london forces strong?
No they are the weakest forces between molecules
Why do melting and boiling points increase down group 7?
London forces are stronger
As the number of electrons increases
Therefore more energy required to break intermolecular forces
What happens to electronegativity as you descend group 7?
Decreases due to an increase in atomic radius.
More shells and therefore more shielding.
Definition of electronegativity.
The ability of an atom to attract the pair of electrons in a covalent bond.
What 3 factors effect electronegativity?
Nuclear charge
Size of atomic radius
Electronic shielding
Why does hydrogen fluoride have an unusually high boiling point?
Due to the hydrogen bonding between the molecules
What is the colour of iodine gas?
purple
