group 7

Question 1

color of halogens at room temperature

Answer 1

flourine- pale yellow gas
chlorine- green gas
bromine- red brown liquid
iodine- black solid

Question 2

halogens properties

Answer 2

get more dense as you go down the group, have a ‘swimming bath smell’, get darker

Question 3

trend in melting point in group 7

Answer 3

the melting point increases going down group 7, as the size of the vanderwaal forces increases

Question 4

trend in reducing agents for halides

Answer 4

as you go down group 7 it is easier to lose an electron and become a halide ion, therefore as you go down the halides become better reducing agents, as they get oxidized more easily

Question 5

what happens with you react a sodium halide with concentrated sulfuric acid

Sodium Chloride

Answer 5

misty fumes will form due to the hydrogen halide, such as HF, HBr, HI etc
NaCl + H2SO4 —> HCl + NaHSO4
there will be no further reaction for this, as chlorine is a weak reducing agent

Question 6

reactions that occur for sodium bromide

Answer 6

firstly the brown misty fumes will form, due to HBr
also because bromide is a stronger reducing agent
another reaction will occur where SO2 will form when hydrogen bromide reacts with concentrated sulfuric acid

Question 7

how to know if SO2 is present

Answer 7

pungent smell

Question 8

what is the sign of Br2

Answer 8

orange vapor