Which uses of iron are due to its chemical properties

Explanation:

Iron has many uses but as far its chemical properties and the given options are concerned, following uses of iron are due to its chemical properties:

* When iron is put into fire, it produces sparks which are colored, which are not produced by mostly metals. Its purely because of the chemical properties it possess.

* When iron is placed in the water and oxygen, it rusts. When we place iron outside in the open air, when it is thrown some water, after few days you will see that iron has started rusting. This process is purely depends on the iron's chemical properties.

question - in 1827, john walker, a druggist in a small english town, tipped a splint with sulphur, chlorate of potash, and sulphid of antimony, and rubbed it on sandpaper, and it burst into flame. the druggist had discovered the first friction-chemical match, the kind we use to-day. it is called friction-chemical because it is made by mixing certain chemicals together and rubbing them. although walker's match did not require the bottle of acid, nevertheless it was not a good one. it could be lighted only by hard rubbing, and it sputtered and threw fire in all directions. in a few years, however, phosphorus was substituted on the tip for antimony, and the change worked wonders. the match could now be lighted with very little rubbing, and it was no longer necessary to have sandpaper upon which to rub it. it would ignite when rubbed on any dry surface, and there was no longer any sputtering. this was the phosphorus match, the match with which we are so familiar. according the paragraph what was the benefit of the new phosphorus match? it burst into flame when rubbed on sandpaper. it was made by mixing chemicals. it could be ignited on any dry surface. it threw fire in all directions.

answer - matches required natural chemicals