Redox reactions in Group 7: disproportionation reactions Flashcards
disproportionation is
the simultaneous oxidation and reduction of an element in a single reaction
chlorine water is
chlorine dissolved in water
bromine water is
bromine dissolved in water
when chlorine dissolves in water, two things happen
- the dissolved chlorine forms chlorine water
- some of this dissolved chlorine reacts to form a mixture of two acids
the two acids formed when chlorine dissolves in water are
- hydrochloric acid
- chloric(I) acid (old name is hypochlorous acid)
the formulae for hydrochloric and chloric(I) acids are:
- HCl
- HOCl or HClO
the equation which shows what happens when chlorine dissolves in water is
Cl2 + H2O = HCl + HClO
use the equation for the dissolving of chlorine in water to show that chlorine undergoes disproportionation
Cl2 + H2O = HCl + HClO
0 -1 +1
when chlorine is added to a cold solution of dilute sodium hydroxide, it reacts to form
form a salt of the acids hydrochloric and chloric(I).
NaCl and NaClO (as well as water)
use the equation for the reaction between chlorine and dilute aqueous sodium hydroxide to show that chlorine is disproportionated
Cl2 + 2NaOH = NaCl + NaClO + H2O
0 -1 +1
sodium chlorate(I) (NaClO) is used as………………and is common in household……………..
used as a disinfectant and found in household bleach
when chlorine is added to hot concentrated sodium hydroxide solution, it reacts to form
sodium chloride and sodium chlorate(V)
NaCl and NaClO3
use the equation for the reaction between chlorine and hot concentrated sodium hydroxide solution to show chlorine is disproportionated
3Cl2 + 6NaOH = 5NaCl + NaClO3 + 3H2O
0 -1 +5
reduction is when the oxidation number
decreases
oxidation is when the oxidation number
increases