Sulphur dioxide and Sulphur trioxide images

Sulphur trioxide linear chain ploymer picture
Sulphur trioxide cyclic trimer picture
Sulphur trioxide picture
Sulphur dioxide pictureRelated article sulphur dioxide

Pictrures of oxyacids of chlorine

chloric(1)acid image
chloric(6)acid image
chloric(5)acid image
chloric(3)acid imageFor more details about oxyacids of chlorine

Sodiumthiosulphates (Na2S2O3.5H2O)

It is prepared by boiling sulphur with an aqueous solution of sodium sulphate
Na2SO3 + 1/8 S8 ------> Na2S2O3
Sodium thiosulphate is a water soluble crystalline substance.
a) Reaction with iodine
Sodium thiosulphate is oxidised by iodine to form sodium tetra thionate. This reaction is the basis of iodometric titrations.
2Na2S2O3 + I2 ---------> Na2S4O6 + 2NaI
b) Reaction with chlorine
Sodium thiosulphate can remove excess chlorine by forming HCl. Hence it is used as an antichlor.
Na2S2O3 + Cl2 + H2O -----------> Na2SO4 + 2HCl + S
c) Reaction with silver halides
Silver halides dissolve in sodium thiosulphate solution due to formation of a complex sodium argento thiosulphate. This reaction is the basis of its use in photography as fixer.
AgCl + Na2S2O3 -------------> NaAgS2O3 + NaCl

Oxides of sulphur

The stable oxides of sulphur are sulphur dioxide (SO2) and sulphur trioxide (SO3)
Sulphur when burnt in air form sulphur dioxide.
S8 + 8O2 -------------> 8SO2
SO2 is a gas at room temperature. It exists as descrete SO2 molecule with angular structure. SO3 is an acidic oxide and exist as planar triangular molecule in gas phase. In solid state, SO3 exist either as cyclic trimer or linear chain polymer.