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

Question 17. A shiny brown coloured element ‘X’ on heating in air becomes black in colour. Write the name the element ‘X’ and the black coloured compound formed.
Answer: The shiny brown coloured element 'X' is copper and the black coloured compound formed is Copper oxide. The reaction involved is