Halogens

describe the trend in mp and bp

• increases

• molecules become larger to more vdw forces

Which molecules can Cl2 replace

bromide and iodide ions

what are the colour of solutions for the halogens

chlorine - pale green

bromine - yellow

iodine - brown

whats the observation when KCl reacts with Br2

yellow solution - no reaction as if doesnt displace it so Br2 is left

describe the trend in reducing agents

increases - more readily loses electrons due to distance

what is the observation of flourine in room temp

pale yellow gas

what is the observation of chlorine in room temp

pale green gas

what are the observations of bromine in room temp

red liquid

gives off brown/orange poisonous fumes

what are the observations of iondine in room temp

shiny black solid

sublimes to purple gas (solid to gas)

give the equation of NaF/Cl with H2SO4 and its observations

NaF/Cl + H2SO4 → NaHSO4 + HF/Cl

white fumes

give the equation of NaBr with H2SO4 and its observations

Acid-base step - NaBr + H2SO4 → NaHSO4 + HBr

Redox step - 2H+ + Br- + H2SO4 → Br2 + SO2 + 2H2O

Overall reaction - 2NaBr + 3H2SO4 → 2NaHSO4 + SO2 + Br2 + 2H2O

white steamy fumes and orange fumes

give the equation of NaI with H2SO4 and its observations

NaI + H2SO4 → NaHSO4 + HI

2H+ + 2I- + H2SO4 → I2 + SO2 + 2 H2O

6H+ + 6I- + H2SO4 → 3I2 + S+ 4 H2O

8H+ + 8I- + H2SO4 → 4I2 + H2S + 4 H2O

white steamy fumes of HI

black solid and purple fumes of I

yellow solid of sulfur, H2S rotten egg smell

give the equation for chlorine with water

Cl2+ H2O ⇌ HClO + HCl

give the equation for chlorine with water in sunlight

2Cl2 + 2H2O → 4H+ + 4Cl - + O2

give one use of chlorine

water treatment to kill anti-bacteria

treatment for drinking water

give the equation of chlorine reacting with cold NaOH solution

Cl2 + 2 NaOH → NaCl + NaClO + H2O