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Mention the names of various steps involved in the extraction of pure metals from their ores.

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Electrochemical Principles of Metallurgy

Explain the following term

Flux

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: General Principles and Processes of Isolation of Elements >> Principles and Methods of Extraction - Concentration

Which among the following reactions is an example of a zero order reaction?

a) `H_(2(g)) + I_(2(g)) -> 2HI_(g)`

b) `2H_2O_(2(l)) -> 2H_2O_(l) + O_(2(g))`

c) `C_12H_22O_(11(aq)) + H_2O_(l) -> C_6H_12O_(6(aq)) + C_6H_12O_(6(aq))`

d) `2NH_(3g)`   `N(2g) + 3H_(2(g))`

Appears in 1 question paper
Chapter: [6] Chemical Kinetics
Concept: Half Life Period of a Reaction

Which among the following minerals does NOT contain aluminium?

(a) Cryolite

(b) Siderite

(c) China clay

(d) Corundum

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Occurrence of Metals

Explain the following methods to protect metals from corrosion:

Galvanization

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Occurrence of Metals

Explain the following methods to protect metals from corrosion:

Passivation

 

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Occurrence of Metals

Which one of the following oxidation state of Manganese is unstable?

(a) + 2

(b) + 4

(c) + 5

(d) + 7

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Oxidation Reduction

In Van Arkel method of refining metal, impure zirconium is converted to unstable volatile
compound by heating it with _______.

(A) oxygen

(B) chlorine

(C) bromine

(D) iodine

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: General Principles and Processes of Isolation of Elements >> Principles and Methods of Extraction - Concentration

Describe ‘froth floatation process’ for concentration of sulphide ore.

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Refining of Crude Metals

Write features of Ellingham's diagrams

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Thermodynamic Principles of Metallurgy

The chemical formula of willemite is __

(a) ZnS

(b) ZnCO3

(c) ZnO

(d) Zn2SiO4

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Occurrence of Metals

The half-life period of zero order reaction A → product is given by

(a) `([A]_0)/k`

(b) `0.693/k`

(c) `[A]_0/(2k)`

(d) `(2[A]_0)/k`

Appears in 1 question paper
Chapter: [6] Chemical Kinetics
Concept: Half Life Period of a Reaction

Write the chemical equations involved in van Arkel method for refining zirconium metal.

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Refining of Crude Metals

What is the action of carbon on the following metal oxides:

Fe2O3 in the blast furnace

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Oxidation Reduction

What is the action of carbon on the following metal oxides :

ZnO in the vertical retort furnace

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Oxidation Reduction

In Van Arkel method for refining zirconium or titanium, the halogen used is __________.

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: General Principles and Processes of Isolation of Elements >> Principles and Methods of Extraction - Concentration

The half life period of a first order reaction is 6. 0 h . Calculate the rate constant

Appears in 1 question paper
Chapter: [6] Chemical Kinetics
Concept: Half Life Period of a Reaction

What is the role of the following compound- 
SiO2 in the extraction of copper from copper pyrites?

Appears in 1 question paper
Chapter: [6] General Principles and Processes of Isolation of Elements
Concept: Occurrence of Metals

In a first-order reaction A → product, 80% of the given sample of compound decomposes in 40 min. What is the half-life period of the reaction? 

Appears in 1 question paper
Chapter: [6] Chemical Kinetics
Concept: Half Life Period of a Reaction

Answer the following in one or two sentences.

What is the relationship between coefficients of reactants in a balanced equation for an overall reaction and exponents in the rate law? In what case the coefficients are the exponents?

Appears in 1 question paper
Chapter: [6] Chemical Kinetics
Concept: Molecularity of Elementary Reactions
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