Please enable JavaScript.
Coggle requires JavaScript to display documents.
(C) Group 2 + Group 7 Elements (Group 2 (Reaction rate examples (Slow Mg…
(C) Group 2 + Group 7 Elements
Group 2
Reactivity down the group
Increases
down the group as outer electron can
escape
more
easily
AR
Increases
Electron shielding
increases
Nuclear charge
negligible
Reaction rate examples
Slow
Mg + H₂O reaction
Fast
Ca + H₂O reaction
Alkalinity
Increases down the group
Lower attraction
to
OH⁻ ions
, so there's more
Group 7
Reactivity down the group
Decreases
down the group as it's
harder
for atom to
attract electrons
AR
increases
Electron shielding
increases
Nuclear charge
negligible
Displacement
More reactive
halogen
replaces weaker
halogen
Cl₂ + 2Br⁻ → Br₂ + 2Cl⁻
(ionic equation to show displacement)
Colours
In water
Chloride =
pale yellow
Bromide =
orange
Iodine =
brown
Water is
polar
In cyclohexane
Chloride =
pale yellow
Bromide =
orange
Iodine =
purple / violet
Cyclohexane is
non-polar
Ionic radius:
Radius of an atom when
gaining/losing
an electron
Increases down the group