Question

A shiny brown coloured element X on heating in air becomes black in colour. name the element X and the black coloured compound formed​

Answer 1

Answer:

The shiny elements are metals. The brown coloured metal is copper. Hence X is copper and the black coloured compound formed is Copper oxide. The reaction involved is:

2Cu(s)+O2(g)→CuO(s)

Answer 2

Copper oxide

The brown coloured metal is copper. Hence ′X′ is copper and the black coloured compound formed is Copper oxide.