Sodium thiosulphate is added in photography to

Options

(a) improve colour of photograph
(b) remove unreacted AgBr
(c) form latent image
(d) to form a better picture

Correct Answer:

remove unreacted AgBr

Explanation:

AgBr + 2 Na₂S₂O₃ → Na₃ [Ag (S₂O₃)₂] + NaBr
Solution of sodium thiosulphate is used as fixer. It forms a soluble complex with silver halides. After fixing, the film can safely be brought out into daylight.