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

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Ques 17: : A shiny brown-coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black coloured compound formed.  


Ans 17: ‘X’ is copper (Cu) and the black-coloured compound formed is copper oxide (Cu O). 


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