Mischmetal is an alloy of lanthanoid metals with Fe.
It consists of a lanthanoid metal (~95%) and iron (~5%) and traces of S, C, Ca, and Al.
Therefore, the correct option is (1).View Full Answer(1)
(a) W(VI) is more stable than Cr(VI). It is true and given in NCERT.
(b) in the presence of HCl permanganate titrations provide satisfactory results. It is incorrect.
Permanganate titrations in presence of hydrochloric acid are unsatisfactory since hydrochloric acid is oxidised to chlorine.
(c) Some individual Ln oxides are used as phosphors in television screens and similar fluorescing surfaces.
So,(b) is incorrect.
Therefore, the correct option is (3).View Full Answer(1)
The reaction of white phosphorus on boiling with alkali in the inert atmosphere resulted in the formation of the product 'A'.
The reaction 1 mol of 'A' with an excess of AgNO3 in an aqueous medium gives 4 moles of Ag.
Ans = 4View Full Answer(1)
On a small scale ammonia is obtained from ammonium salts which decompose when treated with caustic soda or calcium hydroxide.
Recovery of NH3
Therefore, the Correct option is (2)View Full Answer(1)
Mutual relationships can be anything.
Li–Mg, B–Si, Be–Al show diagonal relationship but Li and Na do not show diagonal relationship as both belongs to the same group and not placed diagonally.
Therefore, the Correct option is (4)View Full Answer(1)
Given below are two statements : Statement I : The value for is Statement II : is more stable in state than state. In the light of the above statements, choose the most appropriate answer from the options given below :
Option: 1 Both statement I and statement II are correct
Option: 2 Both statement I and statement II are incorrect
Option: 3 Statement I is incorrect but statement II is correct
Option: 4 Statement I is correct but statement II is incorrect
The Eo value for Ce4+/Ce3+ is +1.74 V because the most stable oxidation state of lanthanide series elements is +3.
It means Ce3+ is more stable than Ce4+View Full Answer(1)
A group 15 element, which is a metal and forms a hydride with strongest reducing power among group 15 hydrides. The element is :
Option: 1 Bi
Option: 2 As
Option: 3 Sb
Option: 4 P
N, P are Non-Metal
As, Sb are Metalloid
Bi is Metal
Hydrides of group 15 elements are
NH3 , PH3 , AsH3 , SbH3 , BiH3
In NH3, the hydrogen atom gets a partial positive charge due to less electronegativity. But in BiH3, the hydrogen atom gets a partial negative charge because hydrogen is more electronegative than bismuth.
BiH3 is a strong reducing agent than others because we know that H- is a strong reducing agent and Bi – H bond dissociation energy is very less.View Full Answer(1)
Given below are two statements : Statement I : Both CaCl2.6H2O and MgCl2.8H2O undergo dehydrationon heating. Statement II : BeO is amphoteric whereas the oxides of other elements in the same group are acidic. In the light of the above statements, choose the correct answer from the options given below :
Option: 1 Statement I is false but statement II is true
Option: 2 Both statement I and Statement II are false
Option: 3 Statement I is true but statement II is false
Option: 4 Both statement I and Statement II are true
The dehydration of hydrated chloride of calcium can be achieved. The corresponding hydrated chloride of magnesium on heating suffer hydrolysis.
MgO, CaO, SrO, BaO All are basic oxides.
So, Both Statement I and Statement II are falseView Full Answer(1)
Assertaion and Reasoning question: (i) Both Assertion (A) and Reason (R) are correct statements, and Reason (R) is the correct explanation of the Assertion (A). (ii) Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). (iii) Assertion (A) is correct, but Reason (R) is incorrect statement. (iv) Assertion (A) is incorrect, but Reason (R) is correct statement. Assertion (A) : F – F bond in F2 molecule is weak. Reason (R) : F atom is small in size
(ii) Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A).View Full Answer(1)
The image distance from the eye lens in the normal eye when we increase the distance of an object from the eye
Option: 1 increases.
Option: 2 decreases.
Option: 3 remains unchanged.
Option: 4 depends on the size of the eyeball.
The image distance from the eye lens in the normal eye when we increase the distance of an object from the eye remains unchanged.View Full Answer(1)
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Atoms and Molecules
Structure of the Atom
The Fundamental unit of Life
The Living Organisms Characteristics and Habitats
The Triangles and its Properties
The Human Eye and the colorful world
The S Block Elements
The P Block Elements (Group 13 and Group 14)
Some basic concepts of Chemistry
Structure of Atom
Classification of Elements and Periodicity in Properties
Chemical Bonding and Molecular Structure
States of Matter
The S-Block Elements
The P-Block Elements
Organic chemistry- some basic principles and techniques
Relations and Functions
The d and f block elements
Principle of Mathematical Induction
Complex Numbers and Quadratic equations
Permutations and Combinations
Sequences and Series
Introduction to Three Dimensional Geometry
Limits and Derivatives
The Living World
Cell: The Unit of Life
Relations and Functions
Inverse Trigonometric Functions
Continuity and Differentiability
Application of Derivatives
Three Dimensional Geometry
The Solid State
General Principles and Processes of isolation of elements
The P-block elements
The d and f block elements
Haloalkanes and Haloarenes
Alcohols, Phenols and Ethers
Aldehydes, Ketones and Carboxylic Acids
Chemistry in Everyday life
Reaching the Age of Adolescence
Stars and The Solar System
The d-and f-Block Elements
THE P - BLOCK ELEMENTS