Answer:
Nitric acid decomposes sodium cyanide and sodium halide. else, they precipitate in test and misguide the result. Therefore, dilute nitric acid is added before testing halogens to expel all the gases if evolved.
Your skin is a tougher substance
The answer to your question would be D) chemical bonding because when you are bonding atoms to each other you are creating a new and unique substance
The concentration of reactants is always equal to the concentration of products