This set of Iron Making Multiple Choice Questions & Answers (MCQs) focuses on “Reactions in Hearth”.
1. CaO is a much more powerful base and desulphuriser than MgO.
a) True
b) False
View Answer
Explanation: CaO is a much more powerful base and desulphuriser than MgO—about 100 times stronger. Bases are electron acceptor. Desulpurisers remove sulphur from the compound.
2. For adequate desulphurisation the oxygen content of the metal should be very low.
a) True
b) False
View Answer
Explanation: For adequate desulphurisation, the oxygen content of the metal should be very low. This is achieved in the blast furnace hearth by the reaction of dissolved oxygen in the hot metal with strong oxide formers: C, Si, Mn dissolved in liquid metal.
3. In the hearth, the slag–metal sulphur reaction is written as – [S] + (O2–) = (S2–) + [O].
a) True
b) False
View Answer
Explanation: In the hearth, the slag–metal sulphur reaction is written in general ionic form as [S] + (O2–) = (S2–) + [O]. In this reaction sulphur replaces oxygen and form S2– ion.
4. For silicon, the slag–metal reaction is: (SiO2) + 2[C] = [Si] + 2CO(g), logK = -30935/T + 20.455, the value of K at T = 1500°C is ____________
a) 1016.248
b) 2135.214
c) 1021.256
d) 265.454
View Answer
Explanation: Given logK = -30935/T + 20.455 and T = 1500°C = 1773°C,
⇒ logK = 3.007
⇒ K = 1016.248.
5. logfSi = WC × eSiC + WSi × eSiSi, WC = 4wt%, eSiC = 0.18, WSi = 0.8wt%, eSiS = 0.103, find fSi.
a) 34.994
b) 54.712
c) 55.145
d) 24.235
View Answer
Explanation: Given logfSi = WC × eSiC + WSi × eSiSi, WC = 4wt%, eSiC = 0.18, WSi = 0.8wt%, eSiS = 0.103
⇒ logfSi = 4 × 0.18 + 0.8 × 0.103
⇒ logfSi = 1.544
⇒ fSi = 34.994.
Sanfoundry Global Education & Learning Series – Iron Making.
To practice all areas of Iron Making, here is complete set of 1000+ Multiple Choice Questions and Answers.