Question

Which element is found in the free state?
(A)Iodine
(B)Sulphur
(C)Phosphorus
(D)Magnesium

Answer 1

A reactivity series has been developed on the basis of the displacement reactions of metals with other metal salts. Some metals are highly reactive, some are moderately reactive and some are the least reactive.

Complete answer: Some elements have least reactivity that they can be even found in free state. Some examples of such elements are gold, copper, silver and platinum. The two metals gold and platinum are not found in a combined state. Copper and silver can be found in combined states even though they come under least reactive elements. They are found in their oxide and sulphide ores. The metals that present at the top of reactivity series are very reactive and they can never be found in nature as free elements. The reactivity series of metals shows the metals in the order of decreasing reactivity of metals. A metal can be considered as more reactive if it reacts with other substances more vigorously and it loses electrons more easily to form cations. Among the given options, sulphur is found in its free state i.e. as ${S_8}$
Therefore, option B is the correct answer.

Note:
The reactivity series is very useful to solve problems involving single displacement reactions. It is used to find out the products of single displacement reactions where a metal replaces another metal in the solution if the first metal is higher in the reactivity series.