Name two salts that are used in black and white photography.

Name the salts that are used in black and white photography. Give reactions when they are exposed to light . Define the type of chemical reaction taking place.

A metal salt MX when exposed to light splits up to form metal M and a gas X_(2) . Metal M is used in making ornaments whereas gas X_(2) is used in making bleaching powder. The salt MX is itself used in black and white photography. (a) What do you think metal M is ? (b) What could be gas X_(2) ? (c) Name the metal salt MX. (d) Name any two salt solutions which on mixing together can produce a precipitate of salt MX. (e) What type of chemical reaction takes place when salt MX is exposed to light ? Write the equation of the reaction.

Read the given passage and answer the questions. In the following chemical reaction "zinc oxide reacts with carbon to produce zinc metal and carbon monoxide." ZnO +C to Zn + CO The reactions used in black and white photography: