the halogens Flashcards
Boiling point of halogen as we go down
Increases
London forces increases due to the increasing mass and relative mass of the atoms.
Physical state of group 7 as we go down
Gas to solid
What happens to group 7 electronegativity as we go down
decreases
atom gets larger
Distance between outer electron and nucleus increase
Also more shielding
What do you use the displacement reaction to show
reactivity of halogens decreases down
What is added to see a clearer colour change
cyclohexane
what is disproportionation
redox reaction in which the same element is both oxidised and reduced eg chlorine with water or cold sodium hydroxide
why chlorine in drinking water may be dangerous
react with organic hydrocarbons which may cause cancer
chlorine + water
Hcl and HCLO
what is HCLO used for
kill bacteria in wotar
what is the chemical formula for bleach
NaCLO
what is reacted to make bleach and what else is formed
Cl2 and cold NaOH NACL, NaCLo and H20
what does reacting WARM NaOH with Cl2 make
NaCl , NaClO3 and H20
halogen boiling point trend and why
increases down group
increase in london forces
more electrons
colour of iodine,chlorine and bromine during displacement
iodine - purple / brown
br - orange
cl - green/yellow
