Silver chloride is stored in dark coloured bottles. give reason

Silver chloride is a light-sensitive chemical compound andit easily undergoes photolytic decomposition reaction. Silver chloride decomposes into silver and chlorine gas when exposed to sunlight. Hence Silver chloride is stored in dark-colored bottles.

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

elements make up everything, and they combine to make compounds.

the answer is c