In the formation of SO2 and SO3 the ratio of the weight of oxygen which combines with 10kg of sulphur is ?

Explanation:

So,0.3125 * 10 ^3 moles of Sulphur combines with 0.3125 * 10^3 moles of Oxygen to from SO2. Therfore mass ratio of SO2 : SO3 = 10 : 15 = 2:3.

its weight is greatest on earth

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.