pt:
Cu + 4HNO3 → Cu(NO3)2 + 2H2O + 2NO2 (1)
3Cu + 8HNO3 → 3Cu(NO3)2 + 4H2O + 2NO (2)
gọi n NO=x n NO2=y
(1) => n Cu = 1/2 n NO2 = 1/2 y
(2) => n Cu = 3/2 n NO = 3/2x
3/2x + 1/2 y = 6,4/64=0,1(A)
M hh khí = 30x + 46y / x+y = 18 * 2 = 36
=> 6x - 10y = 0 (B)
(A)(B)=> x=0,05 y...