Iron becomes passive by ..................... due to formation of .....................
dil. $HCl, Fe_2O_3$
$80\%$ conc. $HNO_3, Fe_3O_4$
conc. $H_2SO_4, Fe_3O_4$
conc. $HCl, Fe_3O_4$
Which metal is present in brass, bronze and German silver
Which of the following pair will have effective magnetic moment equal
When ammonia is added to a cupric salt solution, the deep blue colour is observed it is due to the formation of
Which of the following is the correct sequence of atomic weights of given elements