(i) If vapour of dry ammonia gas are brought in contact with red litmus strip, what will happen to the colour of the litmus strip?
(ii) Name the metal whose foils are used for the packing of food materials.
(i) The colour of the litmus strip will remain unchanged because ammonia (NH3) does not act as a base in the absence of water.
(ii) Aluminium foils are used for the packing of food materials.