During the reaction of copper metal with concentrated hno3 one of the products of the reaction is a dense, toxic and red-brown gas. what is the formula of this gas?

Respuesta :

The reaction between HNO₃ and Cu is characterised by the reaction:
         Cu  +  4HNO₃  →  Cu(NO₃)₂  +  2NO₂  +  2H₂O

Now, the formula of the thick gas produced that is toxic, and red-brown is actually Nitrogen Dioxide (NO₂).