Halogens Flashcards
(18 cards)
What colour is Cl when dissolved in water?
Virtually colourless
What colour is Br when dissolved in water?
Yellow/orange
What colour is I when dissolved in water?
Brown
What colour is Cl when dissolved in hexane?
Virtually colourless
Why do halogens have low solubility?
They are diatomic molecules so are non-polar.
What colour is Br when dissolved hexane?
Orange/red
What colour is I when dissolved in hexane?
Pink/violet
Why does reactivity decrease as you go down the group in halogens?
Atoms become larger, outer electrons further from nucleus, outer electrons shielded more from positive attraction of nucleus, harder for larger atoms to attract electron needed to form ion.
Why does electronegativity decrease as you go down the group?
More shielding, more distance between nucleus and bonding electrons, larger atomic radii and less charger.
Why does bp and mp increase down the group?
More electrons, more London forces, harder to overcome/break intermolecular forces.
What will Cl displace? (Cl2)
Bromide and iodide (Br- and I-)
What will bromine displace? (Br2)
Iodide (I-)
Not Cl
What will iodine displace? (I2)
Neither Cl- or Br- ions
What colour change will occur if bromide is displaced and bromine is formed?
Orange
What colour change will occur if iodide is displaced and iodine is formed?
Brown
What happens when halogens react?
They’re reduced and they oxidise other substances
What is produced when group 1 and 2 metals react with halogens?
Halide salts
What form are the halogens in in their physical state?
Gases
