nNO = 1.2
FeS2 => Fe2(SO4)3
a----------------3a/2
Cu2S => CuSO4
b-------------2b
2a + b = 3a/2 + 2b ( bt nguyên tố S)
=> a =2b
Áp dụng đl bt e
N+5 + 3e = N+2
--------3.6----1.2
FeS2 = Fe3+ + 2S+6 + 15e
a-------------------------------15a
Cu2S = 2Cu2+ + S+6 + 10e
a/2----------------------------5a
15a = 3.6 => a = 0.24
=> m = 0.36*400 + 0.24*160=182.4g