C6 Groups in the periodic table Flashcards
What is the state and colour of chlorine at room temperature?
- gas
- pale green
What is the state and colour of bromine at room temperature?
- liquid
- reddish brown
What is the state and colour if iodine at room temperature?
- solid
- grey
What is the colour if iodine in gaseous state?
violet
What is the name of elements in Group 7?
halogens
What happens to the melting+boiling points of group 7 as you go down the group?
increases
What happens to state of matter as you go down group 7?
gas –> liquid –> solid
What happens to the colour as you go down group 7?
darkens
What happens to the density as you go down group 7?
increases
What happens to group 7 elements’ reactivity as you go down the group?
decreases
Why does group 7 elements’ reactivity decrease as you go down the group?
- as you go down group 7, atoms get larger
- outer electrons become further from nucleus
- force of attraction between nucleus and the outer electrons decreases
- harder to attract more electrons to fill outer shell
What is the test for chlorine gas?
- damp,blue litmus paper
- turns red then bleach white if chlorine is present
What is formed when halogens react with metals?
halogen + metal –> metal halide
What does halogens reacting with hydrogen form?
halogen + hydrogen –> hydrogen halide
Hydrogen halides are _______ meaning when they dissolve they form ______ solutions (they contain __ ions)
- soluble
- acidic
- H+
What colour would an acidic solution turn if universal indicator was added?
red/orange/yellow
Why are halogen reactions considered to be displacement reactions?
- more reactive group7 element
- displaces
- less reactive group7 element
-from solution of its salts
What is the difference between oxidisation and reduction?
OIL RIG
Oxidation
Is
Loss of electrons
Reduction
Is
Gain of electrons
What must occur in redox reactions?
oxidisation and reduction
What are oxidation-reduction reactions called?
redox reactions
6 marker:
The order of reactivity of chlorine, bromine and iodine can be determined by carrying out displacement reactions.
Explain how displacement reactions can be used to show the reactivity of these three elements.
order of reactivity:
chlorine > bromine > iodine
suitable experiments:
chlorine>bromine
-add chlorine to solution of potassium bromide
-solution turns orange/yellow
-bromine is produced/[balanced equation]
-so chlorine is more reactive as it displaces bromine /oxidises bromide ions
bromine>iodide
- add bromine to solution of potassium iodide
- solution turns yellow/red/brown
- iodine is produced/[balanced equation]
- bromine is more reactive as it displaces iodine /oxidises iodide ions
chlorine>iodine
- add chlorine to solution of potassium iodide
- solution turns yellow/red/brown
- iodine is produced/[balanced equation]
- chlorine is more reactive as it displaces iodine /oxidises iodide ions
