SATHEE: Some Basic Principles Of Organic Chemistry Question 229

Some Basic Principles Of Organic Chemistry Question 229

Question: In which of the following pair of metals, both are commercially extracted from their respective ores by self- reduction method?

Options:

A) Zn, Cu

B) Pb, Cu

C) Sn, Zn

D) Al, Ag

Show Answer

Answer:

Correct Answer: B

Solution:

(i) Extraction of tin (carbon reduction): $S n O_{2} + 2 C \to S n + 2 C O$

(ii) Extraction of zinc (carbon reduction): $Z n O + C \overset{c o k e, 673}{\to} Z n + C O$

(iii) Extraction of lead (self-reduction): $P b S + 2 O_{2} \to P b S O_{4};$

$P b S + 3 O_{2} \to 2 P b O + 2 S O_{2}$

$P b S + 2 P b O \to 3 P b + S O_{2};$

$P b S + P b S O_{4} \to 2 P b + 2 S O_{2}$

(iv) Extraction of copper (self-reduction): $2 C u F e S_{2} + 4 O_{2} \to C u_{2} S + 2 F e O + 3 S O_{2}$

$C u_{2} S + F e O + S i O_{2} \to F e S i O_{3}$

$(f u s i b l e, s l a g) + C u_{2} S (M a t t e)$

$2 C u_{2} S + 3 O_{2} \to 2 C u_{2} O + 2 S O_{2};$

$2 C u_{2} O + C u_{2} S \to 6 C u + S O_{2}$

(v)Extraction of aluminium (electrolytic reduction, Hall- Heroult process): The purified $A l_{2} O_{3}$ is mixed with $N a_{3} A l F_{6}$ (cryolite) or $C a F_{2}$ , (fluorspar) which lowers the melting point of the mixture and increases conductivity.

The fused matrix is electrolysed.

Cathode: $A l^{3 +}$ (melt) + $3 e^{-} \to A l, (l)$

Anode: $C (s) + O^{2 -}$ (melt) $\to C O (g) + 2 e^{-}$ $C (s) + 2 O^{2 -} (m e l t) \to C O_{2} (g) + 4 e^{-}$

(vi) Extraction of gold/silver (leaching and displacement method): $4 A u / A g (s) + 8 C N^{-} (a q) + 2 H_{2} O (a q) + O_{2} (g)$

$\to 4 {[A u / A g {(C N)}_{2}]}^{-} (a q) + 4 O H^{-} (a q)$

$2 {[A u / A g {(C N)}_{2}]}^{-} (a q) + Z n (s) \to 2 A u / A g (s)$

$+ {[Z n {(C N)}_{4}]}^{2 -} (a q)$

Some Basic Principles Of Organic Chemistry Question 229

Question: In which of the following pair of metals, both are commercially extracted from their respective ores by self- reduction method?

Options:

Answer:

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

Some Basic Principles Of Organic Chemistry Question 229

Question: In which of the following pair of metals, both are commercially extracted from their respective ores by self- reduction method?

Options:

Answer:

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

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