group 7 Flashcards
(69 cards)
what is the physical property of flourine?
- pale yellow gas
- very reactive
- toxic
what is the physical property of chlorine?
- green gas
- very reactive
- poisonous in high concentration
what is the physical property of bromine?
-red liquid
-gives off dense brown/orange poisonous fumes
-often used as a solution in water called bromine water
what is the trend in melting point and boiling point in group 7?
-increases down the group
-more electrons
-larger VDW forces between molecules
-intermolecular force gets larger
-no PD-PD because it has the same element so it cancels out
what is the trend in electronegativity down in group 7?
- decreases
- bigger atoms/ more shells
- more shielding
- weaker attraction between nucleus and 2 electrons in covalent bonds
what is the trend in atomic radius down the group?
- increases
- more shells
- bigger atoms
what is the trend in 1st ionisation?
- decreases
- atoms gets bigger/more shells
- mores shielding
- weaker attraction from nucleus to electron in outer shell
what is the physical property of iodine?
- grey crystals
-reactive
-toxic
-easily turns into purple vapour on heating
-used in solution as antiseptic
what is the effect of a halogen that is strong oxidising agent on a halogen with a lower oxidising power?
it will displace the weaker halogen from one of its compounds
how does oxidising strength change down the group of halogens?
the oxidising strength decreases
what role do oxidising agents play in chemical reactions?
they are electron acceptors
what would chlorine displace?
- bromine ions
- iodine ions
what would bromine displace?
- iodine ions
what would the reaction Cl2 and potassium chloride form?
Very pale green
solution, no
reaction
what would the reaction Br2 and potassium chloride form?
Yellow solution, no
reaction
what would the reaction iodine and potassium chloride form?
Brown solution,
no reaction
what would the reaction potassium bromide and chlorine form?
Yellow solution, Cl
has displaced Br
what would the reaction potassium bromide and bromide form?
Yellow solution, no
reaction
what would the reaction potassium bromide and iodine form?
Brown solution,
no reaction
what would the reaction potassium iodide and chlorine form?
Brown solution, Cl
has displaced I
what would the reaction potassium iodine and bromine form?
Brown Solution, Br
has displaced I
what would the reaction potassium iodine and iodine form?
Brown Solution,
no reaction
what is the colour of chlorine?
very pale green often colourless
what is the colour of iodine?
brown solutions sometimes black solid present