Q38.Given are two statements one is labelled as Assertion and other is labelled as Reason. Assertion: Magnesium can reduce Al2 O3 at a temperature below 1350 °C, while above 1350 °C aluminium can reduce MgO. Reason: The melting and boiling points of magnesium are lower than those of aluminium. In light of the above statements, choose most appropriate answer from the options given below (1) Both Assertion and Reason are correct, and (2) Both Assertion and Reason are correct, but Reason is correct explanation of Assertion. Reason is NOT the correct explanation of Assertion. (3) Assertion is correct Reason is not correct. (4) Assertion is not correct, Reason is correct.
What This Question Tests
This assertion-reasoning question evaluates the understanding of Ellingham diagrams and the thermodynamic feasibility of metal oxide reduction at different temperatures.
Concepts Tested
Formulas Used
ΔG = ΔH - TΔS
📚 NCERT Sections This Tests
2.2 — Given The Standard Electrode Potentials,
Chemistry Class 11 · Chapter 2
2.2 Given the standard electrode potentials, K+/K = –2.93V, Ag+/Ag = 0.80V, Hg2+/Hg = 0.79V Mg2+/Mg = –2.37 V, Cr3+/Cr = – 0.74V Arrange these metals in their increasing order of reducing power.
2.1 — Arrange The Following Metals In The Order In Which They Displace Each Other
Chemistry Class 11 · Chapter 2
2.1 Arrange the following metals in the order in which they displace each other from the solution of their salts. Al, Cu, Fe, Mg and Zn.
4.11 — Explain Giving Reasons:
Chemistry Class 11 · Chapter 4
4.11 Explain giving reasons: (i) Transition metals and many of their compounds show paramagnetic behaviour. (ii) The enthalpies of atomisation of the transition metals are high. (iii) The transition metals generally form coloured compounds. (iv) Transition metals and their many compounds act as good catalyst.
📋 Question Details
- Chapter
- Metallurgy
- Topic
- Ellingham Diagram, Thermodynamics of reduction
- Year
- 2022
- Shift
- 28 Jun Shift 1
- Q Number
- Q38
- Type
- Assertion Reasoning
- NCERT Ref
- Class 12 Chemistry Ch 6: General Principles and Processes of Isolation of Elements
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