ihh

carbon, hydrogen and oxygen

halogens (chlorine, bromine and iodine), sulfur and phosphorous

-arsenic, mercury and other metals

-are only for elements other than the carbon hydrogen

detected qualitatively by heating a mixture of the given substance with dry copper (II) oxide in a glass tube

-indicated by the formation of the white precipitate of two calcium carbonates when the gaseous products are passed through a solution of a lime water.

-indicated by the formation of droplets of water in the tube

-used to test the presence of oxygen -prepared by soaking filter paper in methanol containing equal amount of ferric chloride and ammonium thiocyanate