Group 7

Question 1

HAlogen in room temp

Answer 1

Flurine = pale yellow gas
Chlorine = pale green gas
bromine = red brown liquid
Iodine = balck-gray solid

Question 2

Electronegetivity

Answer 2

decreases down the group

• due to inc in inner shielding and stomic radius
• shared ele pair expereince less nuc att

Question 3

Boiling point

Answer 3

increases down the group

as go dwon halogen molecule have
- more mass
- greater size and surface area
- more electrons

IMF bet diatomic molecules ( van der waals) = more stronger = need more energy to overcome these forces

Question 4

Redox reaction

Answer 4

• gain electron = becomes halide ion (-1)

redox = reaction involves transfer of electron = halogen = oxidising agent

Question 5

Oxidising agent

Answer 5

• oxidises other substants and gets reduced itself (accepts electron)

Question 6

trend of redox agent

Answer 6

• dec as go down the group

I2 +Na = 2NAI
Br2+2NaI= 2NaBr + I2

stronger oxidisng agent takes over from less powerful = displacement reaction

Question 7

reactivity of flurine

Answer 7

• really reactive with water
• other displacement reaxtion can be done in aq solution

Question 8

redox and iodine

Answer 8

• iodine = less able to attract electrons from other atom = easily gets reduced - weaker oxidising agent

weaker att bet nucleus and outer ele can easily be taken out = strong reducing agent

Question 9

acid and base reaction

Answer 9

in all Sodium (flurine, chlorine, bromine and iodine )

produces NaHSO4 + H(element)

Question 10

redox equation

Answer 10

only NaBr and NaI

NABr = SO2 k+ 2H2O + BRs