When FeS2 is burnt in air, it converts to Fe2O3 as, FeS2(s)+O2(g)→Fe2O3(s)+SO2(g), the change in percentage by weight of iron in the process is: (Atomic mass of Fe = 56 u)
A
23% increase
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
12% decrease
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
12% increase
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
No change
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A23% increase FeS2(s)+O2(g)→Fe2O3(s)+SO2(g)
For FeS2, Molecular weight=56+32×2=120u ∴%of Fe=56120×100=46.67%
For Fe2O3, Molecular weight=56×2+3×16=160u ∴%of Fe=112160×100=70% Percentage increase=70−46.67=23.33%