Class 12 Chemistry - Chapter General Principles and Processes of Isolation of Elements NCERT Solutions | Differentiate between "minerals&quo

What is the significance of leaching in the extraction of aluminium?

Write down the reactions taking place in different zones in the blast furnace during the extraction of iron.

Copper can be extracted by hydrometallurgy but not zinc. Explain.

Outline the principles of refining of metals by the following methods:

(i) Zone refining

(ii) Electrolytic refining

(iii) Vapour phase refining

Name the common elements present in the anode mud in electrolytic refining of copper. Why are they so present ?

The reaction,

      Cr₂O₃  +  2Al    →    Al₂O₃  + 2Cr            (ΔG_o = -421kJ)

is thermodynamically feasible as is apparent from the Gibbs energy value. Why does it not take place at room temperature?

How can you separate alumina from silica in bauxite ore associated with silica? Give equations, if any.

Why is the extraction of copper from pyrites more difficult than that from its oxide ore through reduction?

Write chemical reactions taking place in the extraction of zinc from zinc blende.

Describe a method for refining nickel.

For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.

Write the formulas for the following coordination compounds:

(i) Tetraamminediaquacobalt (III) chloride

(ii) Potassium tetracyanonickelate(II)

(iii) Tris(ethane-1,2-diamine) chromium(III) chloride

(iv) Amminebromidochloridonitrito-N-platinate(II)

(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate

(vi) Iron(III) hexacyanoferrate(II)

(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N

(ii) Write IUPAC names of all the isomers.

(iii) What type of isomerism is exhibited by different pairs of amines?

Why are solids rigid?

Write any two characteristics of Chemisorption.

Write the structures of the following compounds.

(i) α-Methoxypropionaldehyde

(ii) 3-Hydroxybutanal

(iii) 2-Hydroxycyclopentane carbaldehyde

(iv) 4-Oxopentanal

(v) Di-sec-butyl ketone

(vi) 4-Fluoroacetophenone

Why are pentahalides more covalent than trihalides?

Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?

Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.

Write structures of the following compounds:

(i) 2-Chloro-3-methylpentane

(ii) 1-Chloro-4-ethylcyclohexane

(iii) 4-tert. Butyl-3-iodoheptane

(iv) 1,4-Dibromobut-2-ene

(v) 1-Bromo-4-sec. butyl-2-methylbenzene

What is the difference between a nucleoside and a nucleotide?

Analysis shows that nickel oxide has the formula Ni_0.98 O_1.00. What fractions of nickel exist as Ni²⁺and Ni³⁺ions?

Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?

How much electricity is required in coulomb for the oxidation of

(i) 1 mol of H₂O to O₂.

(ii) 1 mol of FeO to Fe₂O₃.

Explain how vacancies are introduced in an ionic solid when a cation of higher valence is added as an impurity in it.

Why is BiH3 the strongest reducing agent amongst all the hydrides of Group 15 elements?

Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?

Write the structure of the major organic product in each of the following reactions:

If a current of 0.5 ampere flows through a metallic wire for 2 hours, then how many electrons would flow through the wire?

Distinguish between the terms homopolymer and copolymer and give an example of each.