Group 7 and Redox Flashcards
Properties of F2
Yellow gas
Very reactive
Toxic
Cl2 properties
Green gas
Very reactive
Toxic
Br2 properties and uses
Orange liquid
Very reactive
Toxic
Often used as a solution in water -bromine water Br2(aq)
I2 properties
Grey crystals
Reactive
Toxic
Easily turns into purple vapour on heating
Used in solution as antiseptic
Trend in atomic radius
Atomic radius increases
More shells/more shielding
Bigger atoms
Trend in electronegativity
Electro negativity decreases
Bigger atoms/more shells
More shielding
Weaker attraction between nucleus and 2 electrons in covalent bond
What is electronegativity
The power of an atom to attract the 2 electrons in a covalent bond
Melting and boiling point trend
Increases
Bigger molecules
More VDW forces
Higher mpt/bpt between MOLECULES
Trend in first ionisation energy
Decreases
Atoms get bigger / more shells
More shielding
Therefore weaker attraction from nucleus to electron in outer shell I’m
What is the reaction equation for Cl2 and Br-?
Cl2 + 2 Br- → 2 Cl- + Br2
This reaction shows the conversion of chlorine and bromide ions to chloride ions and bromine.
What color solution forms when bromine is present in aqueous solution?
Yellow solution forms
This indicates the presence of bromine in its aqueous form.
What is the reaction equation for C/2 and I2?
Cl2 + 21- → 2 Cl- + I2
What happens to the solution when Br2 is added to I-?
Brown solution forms
This indicates the formation of iodine in the solution.
What is the reaction equation for Br2 and I-?
Br2 + 2I- → 2 Br- + I2
This reaction results in the formation of bromide ions and iodine.
What color solution does I2 form in aqueous solution?
Brown solution forms
This indicates the presence of iodine in its aqueous form.
What happens to the solution when I2 is present?
Stays brown solution (no reaction)
This indicates that there is no further reaction occurring in the presence of iodine.
What is the state of Br2 in aqueous solution?
Stays yellow solution (no reaction)
This indicates that bromine remains in its aqueous form without reacting further.
What is the trend of oxidising power among halogens?
Cl, > Br2 > I2
This trend indicates that chlorine is the strongest oxidising agent among the three.
What happens when a halogen acts as an oxidising agent?
It gains electrons (taken from the oxidised species)
This process is represented by the equation: X2 + 2e- → 2X.
Fill in the blank: When a halogen gains electrons, the reaction can be represented as _______.
X2 + 2e- → 2X
Why does the ability of halogens to gain electrons decrease down the group?
Atoms are larger & there is more shielding (due to extra electron shell)
This increased distance and shielding makes it harder for halogens to attract additional electrons.
True or False: It becomes easier to gain an electron as you move down the group of halogens.
False
What is the reaction of Cl2 and 2 Br-?
cl2 + 2Br- =2 Cl- + Br2
This reaction indicates the formation of chloride ions and bromine.
What color solution forms in the organic layer when Br2 is produced?
Yellow solution
The yellow solution indicates the presence of bromine in the organic layer.