Topic 6 Flashcards
Done
6.1
Why are alkali metals in group 1?
1 electron on outermost shell
6.2
Give 3 physical properties of alkali metals
-Soft
-Low mp
-Very reactive
6.3
Describe the reaction of lithium with water
-Fizzing
-Moves on water surface
-Dissolves/disappears
6.3
Describe the reaction of sodium with water
-Melts into molten ball
-More fizzing + moves + dissolves faster than Li
6.3
Describe the reaction of potassium in water
-Lilac flame
-Explodes
-More fizzing + moves + dissolves faster than Na
6.4
What happens to the reactivity of alkali metals as you go down the group
Increases
6.4 6.5
Explain the pattern of reactivity of the alkali metals in terms of electronic configurations
-As descend, reactivity increases
-Ions larger
-Greater d between e^- on outermost shell & positive nucleus
-e^- shielding (more e^- = reduce F)
-Electrostatic F of attraction decreases
-e^- lost more easily
6.6
State the colour and physical state of fluorine
Pale yellow gas
6.6
State the colour and physical state of chlorine
Green/yellow gas
6.6
State the colour and physical state of bromine
Yellow/orange solid
6.6
State the colour and physical state of iodine
Grey/black solid
6.6
What colour is iodine vapour?
Purple
6.7
What happens to the appearance of the halogens as you go down group 7?
Darker
6.7
What happens to the boiling point of the halogens as you go down the group? Explain this trend
-Increases
-Molecule size increases
-Stronger intermolecular F between molecules
-More energy needed to separate bonds
6.7
What is a use of fluorine?
Toothpaste
6.7
What is a use of chlorine?
Kill micro-organisms in swimming pools
6.8
What are bromine and iodine used for?
Antiseptics
6.8
Describe the chemical test for chlorine gas
Damp blue litmus paper turns red then bleached
6.9
What is the product when a halogen reacts with a metal?
Metal halide
6.9
State one feature of the halogens in terms of their safety
Toxic