Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter General Principles and Processes of Isolation of Elements. This page offers a step-by-step solution to the specific question from Exercise 2, Question 3: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.
Why is the extraction of copper from pyrites more difficult than that from its oxide ore through reduction?
The Gibbs free energy of formation (ΔfG) of Cu2S is less than that of H2S and CS2. Therefore, H2 and C cannot reduce Cu2S to Cu.
On the other hand, the Gibbs free energy of formation of Cu2O is greater than that of CO. Hence, C can reduce Cu2O to Cu.
C(s) +Cu2O(s) → 2Cu(s) + CO(g)
Hence, the extraction of copper from its pyrite ore is difficult than from its oxide ore through reduction.
The reaction between A and B is first order with respect to A and zero order with respect to B. Fill in the blanks in the following table:
| Experiment |
A/ mol L - 1 |
B/ mol L - 1 |
Initial rate/mol L - 1 min - 1 |
| I | 0.1 | 0.1 |
2.0 × 10 - 2 |
| II | -- | 0.2 |
4.0 × 10 - 2 |
| III | 0.4 | 0.4 | -- |
| IV | -- | 0.2 |
2.0 × 10 - 2 |
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Read MoreWelcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 3: Why is the extraction of copper from pyrites more difficult than that from its oxide ore through red....
Comments
The value of âfG â for formation of Cr2O3 is -540 KJ mol-1 and that of Al2O3 -827 KJ mol-1 . Is the reduction of Cr2O3 possible with Al ?
Ok partha,you try your best
Bahot hi aacha
Nice answer
Nice answer .could hav tried litle mich better