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d and f Block Elements — JEE Main & Advanced Chemistry PYQs

517 previous year questions from d and f Block Elements with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

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1

Given below are two statements: Statement I: The number of pairs among [ Ti ⁴⁺, V ²⁺] , [ V ²⁺, Mn ²⁺] , [ Mn ²⁺, Fe ³⁺] and [ V ²⁺, Cr ²⁺] in which both ions are coloured is 3 . S

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Given below are two statements for catalytic properties of transition metals. Statement I: First row transition metals which act as catalyst utilise their 3d electrons only for

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The correct order of first ( _i H₁) and second ( _i H₂) ionisation enthalpy values of Cr and Mn are : A. _i H₁ : Cr > Mn B. _i H₂ : Cr > Mn C. _i H₁ : Mn > Cr D. _i H₂ : Mn > Cr Ch

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The correct statements among the following are. A. Basic vanadium oxide is used in the manufacture of H ₂ SO ₄ . B. The spin-only magnetic moment value of the transition metal hali

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Given below are two statements : Statement I: Presence of large number of unpaired electrons in transition metal atoms results in higher enthalpies of their atomisation. Statement

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A paper dipped in a dil. H₂SO₄ solution of ' X ' upon treatment with SO₂ gas turns into green. The compound ' X ' is :

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Which of the following is NOT a physical or chemical characteristics of interstitial compounds?

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Pairs of elements with the same number of electrons in their respective 4f orbital are [Atomic number. Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72] A. (Eu and Gd) B. (Dy

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Consider |x| is the difference in oxidation states of Mn in highest manganese fluoride and highest manganese oxide. The ions with |x| number of unpaired electrons from the followin

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The correct statements among the following are, A. Mo(VI) and W(VI) are less stable than Cr(VI) . B. Ce⁴⁺ and Tb⁴⁺ are oxidant while Eu²⁺ and Yb²⁺ are reductant. C. Cm and Am have

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Correct statements from the following are A. Potassium dichromate is an oxidising agent and it oxidises FeSO₄ to Fe₂(SO₄)₃ in acidic medium. B. Sodium dichromate can be used as pri

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Number of paramagnetic ions among the following d- and f-block metal ions is _______. Mn²⁺, Cu²⁺, Zn²⁺, Yb²⁺, Sc³⁺, La³⁺, Gd³⁺, Lu³⁺, Ti⁴⁺, Ce⁴⁺ (Atomic number of Mn = 25, Cu = 29,

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Which of the following sets includes all the species that will change the orange colour of K₂Cr₂O₇ in acidic medium?

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Consider the following statements about manganate and permanganate ions. Identify the correct statements. A. The geometry of both manganate and permanganate ions is tetrahedral. B.

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Given below are two statements: Statement I : The number of pairs, from the following, in which both the ions are coloured in aqueous solution is 3. [ Sc ³⁺, Ti ³⁺ ], [ Mn ²⁺, Cr ²

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" X " is an oxoanion of the lightest element of group 7 (in the periodic table). The metal is in +6 oxidation state in " X ". The color of the potassium salt of X is

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The oxidation state of chromium in the final product formed in the reaction between KI and acidified K ₂ Cr ₂ O ₇ solution is:

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Given below are two statements : Statement I : The first ionization enthalpy of Cr is lower than that of Mn . Statement II : The second and third ionization enthalpies of Cr are hi

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Among the following oxides of 3 d elements, the number of mixed oxides are _ _ _ _ 。 Ti ₂ O ₃, ~V ₂ O ₄, Cr ₂ O ₃, Mn ₃ O ₄, Fe ₃ O ₄, Fe ₂ O ₃, Co ₃ O ₄

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A first row transition metal ( M ) does not liberate H ₂ gas from dilute HCl.1 mol of aqueous solution of MSO ₄ is treated with excess of aqueous KCN and then H ₂ ~S ( ~g ) is pass

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Given below are some of the statements about Mn and Mn ₂ O ₇ . Identify the correct statements. A. Mn forms the oxide Mn ₂ O ₇ , in which Mn is in its highest oxidation state. B. O

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On heating a mixture of common salt and K ₂ Cr ₂ O ₇ in equal amount along with concentrated H ₂ SO ₄ in a test tube, a gas is evolved. Formula of the gas evolved and oxidation sta

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MnO ₄ ²⁻ , in acidic medium, disproportionates to :

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Consider the following reactions: NaCl + K ₂ Cr ₂ O ₇+ H ₂ SO ₄ ~A + KHSO ₄+ NaHSO ₄+ H ₂ O A + NaOH B + NaCl + H ₂ O B + H ₂ SO ₄+ H ₂ O ₂ C + Na ₂ SO ₄+ H ₂ O In the product ' C

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The pair(s) of diamagnetic ions is(are)

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The correct decreasing order of spin only magnetic moment values ( BM ) of Cu ⁺, Cu ²⁺, Cr ²⁺ and Cr ³⁺ ions is :

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' X ' is the number of acidic oxides among VO ₂ , V ₂ O ₃, CrO ₃, ~V ₂ O ₅ and Mn ₂ O ₇ . The primary valency of cobalt in [ Co ( H ₂ NCH ₂ CH ₂ NH ₂ )₃ ]₂ ( SO ₄ )₃ is Y. The valu

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The number of valence electrons present in the metal among Cr , Co , Fe and Ni which has the lowest enthalpy of atomisation is

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The first transition series metal ' M ' has the highest enthalpy of atomisation in its series. One of its aquated ion ( M ^ n ) exists in green colour. The nature of the oxide form

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The incorrect relationship in the following pairs in relation to ionisation enthalpies is :

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Pair of transition metal ions having the same number of unpaired electrons is :

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KMnO ₄ acts as an oxidising agent in acidic medium. ' X ' is the difference between the oxidation states of Mn in reactant and product. ' Y ' is the number of ' d ' electrons prese

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Given below are two statements : Statement I : CrO ₃ is a stronger oxidizing agent than MoO ₃ Statement II : Cr ( VI ) is more stable than Mo ( VI ) In the light of the above state

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Among, Sc , Mn , Co and Cu , identify the element with highest enthalpy of atomisation. The spin only magnetic moment value of that element in its +2 oxidation state is _____ BM (i

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The metal ions that have the calculated spin only magnetic moment value of 4.9 B.M. are A. Cr ²⁺ B. Fe ²⁺ C. Fe ³⁺ D. Co ²⁺ E. Mn ³⁺ Choose the correct answer from the options give

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Consider the following reactions aligned & CrO ₂ Cl _ 2( Vapour ) + NaOH ~B + NaCl + H ₂ O & ~B + H ⁺ C + H ₂ O aligned The number of terminal ' O ' present in the compound ' C ' i

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The molar mass of the water insoluble product formed from the fusion of chromite ore ( ( FeCr ₂ O ₄ ) ) with ( Na ₂ CO ₃ ) in presence of ( O ₂ ) is _______ ( g mol ⁻¹ ).

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The amphoteric oxide among V ₂ O ₃, ~V ₂ O ₄ and V ₂ O ₅ , upon reaction with alkali leads to formation of an oxide anion. The oxidation state of V in the oxide anion is :

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Identify the inorganic sulphides that are yellow in colour : (A) ( NH ₄ )₂ ~S (B) Pbs (C) Cus (D) As ₂ ~S ₃ (E) As ₂ ~S ₅ Choose the correct answer from the options given below :

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The spin only magnetic moment ( ) value (B.M.) of the compound with strongest oxidising power among Mn ₂ O ₃, TiO and VO is ____ B.M. (Nearest integer).

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Which of the following oxidation reactions are carried out by both K ₂ Cr ₂ O ₇ and KMnO ₄ in acidic medium? A. ⁻ I ₂ B. S²⁻ S C. Fe ²⁺ Fe ³⁺ D. ⁻ IO ₃ ⁻ E. S ₂ O ₃ ²⁻ SO ₄ ²⁻ Choo

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Consider ' n ' is the number of lone pair of electrons present in the equatorial position of the most stable structure of ClF ₃ . The ions from the following with ' n ' number of u

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Find the compound ' A ' from the following reaction sequences. A aqua-regia B [ (2) AcOH ] (1) KNO ₂ NH ₄ OH yellow ppt

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Preparation of potassium permanganate from MnO ₂ involves two step process in which the 1st step is a reaction with KOH and KNO ₃ to produce

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Which of the following ions is the strongest oxidizing agent? (Atomic Number of Ce =58, Eu =63, ~Tb =65, Lu =71 )

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Consider the following reactions K ₂ Cr ₂ O ₇ [- H ₂ O ] KOH [ A ] [- H ₂ O ] H ₂ SO ₄ [ ~B ]+ K ₂ SO ₄ The products [A] and [B] , respectively are :

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Match List - I with List - II. array llll & List - I & & List - II (A) & Bronze & (I) & Cu , Ni (B) & Brass & (II) & Fe , Cr , Ni , C (C) & UK silver coin & (III) & Cu , Zn (D) & S

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The correct set of ions (aqueous solution) with same colour from the following is:

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Niobium ( Nb ) and ruthenium ( Ru ) have " x " and " y " number of electrons in their respective 4 d orbitals. The value of x+y is ______ -.

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Lanthanoid ions with 4 f^7 configuration are : (A) Eu ²⁺ (B) Gd ³⁺ (C) Eu ³⁺ (D) Tb ³⁺ (E) Sm ²⁺ Choose the correct answer from the options given below :

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Paragraph: When potassium iodide is added to an aqueous solution of potassium ferricyanide, a reversible reaction is observed in which a complex ( P ) is formed. In a strong acidic

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Paragraph: When potassium iodide is added to an aqueous solution of potassium ferricyanide, a reversible reaction is observed in which a complex ( P ) is formed. In a strong acidic

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Give below are two statements: Statement I : The higher oxidation states are more stable down the group among transition elements unlike p-block elements. Statement II : Copper can

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A transition metal ' ( M ) ' among ( Sc , Ti , V , Cr , Mn ) and ( Fe ) has the highest second ionisation enthalpy. The spin-only magnetic moment value of ( M ⁺ )ion is _______. (

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(0.05 M CuSO ₄ ) when treated with (0.01 M K ₂ Cr ₂ O ₇ ) gives green colour solution of ( Cu ₂ Cr ₂ O ₇ ). The two solutions are separated as shown below : [SPM : Semi Permeable M

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lectronic configuration of ( Cu ( II ) ) is (3 ~d ^9 ) whereas that of ( Cu ( I ) ) is (3 ~d ¹⁰ ). Which of the following is correct?

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Number of colourless lanthanoid ions among the following is ________ ( Eu ³⁺, Lu ³⁺, Nd ³⁺, La ³⁺, Sm ³⁺ )

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Given below are two statements : Statement (I) : Fusion of ( MnO ₂ ) with ( KOH ) and an oxidising agent gives dark green ( K ₂ MnO ₄ ). Statement (II) : Manganate ion on electroly

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Iron (III) catalyses the reaction between iodide and persulphate ions, in which A. ( Fe ³⁺ ) oxidises the iodide ion B. ( Fe ³⁺ ) oxidises the persulphate ion C. ( Fe ²⁺ ) reduces

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The 'spin only' magnetic moment value of ( MO ₄ ²⁻ ) is _______ BM. (Where M is a metal having least metallic radii. among ( Sc , Ti , V , Cr , Mn ) and ( Zn ) ). (Given atomic num

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Arrange the following elements in the increasing order of number of unpaired electrons in it. (A) ( Sc ) (B) ( Cr ) (C) ( V ) (D) ( Ti ) (E) Mn Choose the correct answer from the o

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Total number of species from the following with central atom utilising ( sp ^2 ) hybrid orbitals for bonding is _____. ( NH ₃, SO ₂, SiO ₂, BeCl ₂, C ₂ H ₂, C ₂ H ₄, BCl ₃, HCHO ,

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The number of element from the following that do not belong to lanthanoids is ( Eu , Cm , Er , Tb , Yb ) and ( Lu )

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Among ( CrO , Cr ₂ O ₃ ) and ( CrO ₃ ), the sum of spin-only magnetic moment values of basic and amphoteric oxides is _______ (10⁻² BM ) (nearest integer). (Given atomic number of

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The difference in the 'spin-only' magnetic moment values of ( KMnO ₄ ) and the manganese product formed during titration of ( KMnO ₄ ) against oxalic acid in acidic medium is _____

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The number of ions from the following that have the ability to liberate hydrogen from a dilute acid is _____. ( Ti ²⁺, Cr ²⁺ ) and ( V ²⁺ )

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While preparing crystals of Mohr's salt, dil ( H ₂ SO ₄ ) is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil ( H ₂ SO ₄ )

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The fusion of chromite ore with sodium carbonate in the presence of air leads to the formation of products ( A ) and ( B ) along with the evolution of ( CO ₂ ). The sum of spin-onl

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The metal that shows highest and maximum number of oxidation state is :

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The spin-only magnetic moment value of the ion among ( Ti ²⁺, V ²⁺, Co ³⁺ ) and ( Cr ²⁺ ), that acts as strong oxidising agent in aqueous solution is _______ BM (Near integer). (Gi

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When ( MnO ₂ ) and ( H ₂ SO ₄ ) is added to a salt (A), the greenish yellow gas liberated as salt (A) is :

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A first row transition metal in its +2 oxidation state has a spin-only magnetic moment value of (3.86 BM ). The atomic number of the metal is

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A first row transition metal with highest enthalpy of atomisation, upon reaction with oxygen at high temperature forms oxides of formula ( M ₂ O _ n ) (where ( n =3,4 ), 5). The 's

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What will be the decreasing order of basic strength of the following conjugate bases? ( ⁻ OH , R O , CH ₃ CO O , C I )

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The element which shows only one oxidation state other than its elemental form is :

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Consider the following reaction ( MnO ₂+ KOH + O ₂ A + H ₂ O ). Product ' ( A ) ' in neutral or acidic medium disproportionate to give products ' ( B ) ' and ' ( C ) ' along with w

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The transition metal having highest 3 rd ionisation enthalpy is:

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Which of the following compounds show colour due to d - d transition?

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Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R . Assertion A : In aqueous solutions Cr 2 + is reducing while Mn 3 + is oxidis

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Number of moles of H + ions required by 1 mole of MnO 4 − to oxidise oxalate ion to CO 2 is ______.

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In the reaction of potassium dichromate, potassium chloride and sulfuric acid (conc.), the oxidation state of the chromium in the product is + _______.

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Choose the correct statements from the following A. Mn 2 O 7 is an oil at room temperature B. V 2 O 4 reacts with acid to give VO 2 2 + C. CrO is a basic oxide D. V 2 O 5 does not

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The 'Spin only’ Magnetic moment for [ Ni ( NH 3 ) 6 ] 2 + is______ × 10 – 1 BM. (given = Atomic number of Ni : 28 ) Round off your answer to the nearest integer.

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Identify correct statements from below: A. The chromate ion is square planar. B. Dichromates are generally prepared from chromates. C. The green manganate ion is diamagnetic. D. Da

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The orange colour of K 2 Cr 2 O 7 and purple colour of KMnO 4 is due to

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A and B formed in the following reactions are: CrO 2 Cl 2 + 4 NaOH → A + 2 NaCl + 2 H 2 O A + 2 HCl + 2 H 2 O 2 → B + 3 H 2 O

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Alkaline oxidative fusion of MnO 2 gives " A " which on electrolytic oxidation in alkaline solution produces B . A and B respectively are:

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Diamagnetic Lanthanoid ions are:

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Match List-I with List-II List I (Species) List II (Electronic distribution) A. Cr + 2 i. 3 d 8 B. Mn + ii. 3 d 3 4 s 1 C. Ni + 2 iii. . 3 d 4 D. V + iv. 3 d 5 4 s 1 Choose the cor

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Which of the following acts as a strong reducing agent? (Atomic number : Ce = 58 , Eu = 63 , Gd = 64 , Lu = 71 )

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Which of the following statements are correct about Zn , Cd and Hg ? A. They exhibit high enthalpy of atomization as the d-subshell is full. B. Zn and Cd do not show variable oxida

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In chromyl chloride test for confirmation of Cl – ion, a yellow solution is obtained. Acidification of the solution and addition of amyl alcohol and 10 % H 2 O 2 turns organic laye

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In alkaline medium. MnO 4 - oxidises I - to

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Choose the correct option having all the elements with d 10 electronic configuration from the following:

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Given below are two statements: Statement (I) : In the Lanthanoids, the formation of Ce + 4 is favoured by its noble gas configuration. Statement (II) : Ce + 4 is a strong oxidant

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NaCl reacts with conc. H 2 SO 4 and K 2 Cr 2 O 7 to give reddish fumes (B), which react with NaOH to give yellow solution (C). (B) and (C) respectively are ;

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Given below are two statements : Statement (I) : The 4f and 5f - series of elements are placed separately in the Periodic table to preserve the principle of classification. Stateme

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In the scheme given below, X and Y , respectively, are Metal halide         →   aq .  NaOH          White pre

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In Chromyl chloride, the oxidation state of chromium is + ___________.

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The pair of lanthanides in which both elements have high third-ionization energy is:

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When a solution of mixture having two inorganic salts was treated with freshly prepared ferrous sulphate in acidic medium, a dark brown ring was formed whereas on treatment with ne

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Given below are two statements: Statement I : Aqueous solution of K 2 Cr 2 O 7 is preferred as a primary standard in volumetric analysis over Na 2 Cr 2 O 7 aqueous solution. Statem

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Prolonged heating is avoided during the preparation of ferrous ammonium sulphate to

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Which of the following statements are correct? (A) The M 3 + / M 2 + reduction potential for iron is greater than manganese. (B) The higher oxidation states of first row d-block el

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In chromyl chloride, the number of d-electrons present on chromium is same as in (Given at no. of Ti : 22 , V : 23 , Cr : 24 , Mn : 25 , Fe : 26 )

JEE Main 2023 Solution View → 106

Which halogen is known to cause the reaction given below?

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In ammonium - phosphomolybdate, the oxidation state of Mo is + _ _ _ _ _ _ _

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Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Cu 2 + in water is more stable than Cu + . Reason (R) : E

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Which element is not present in Nessler’s reagent?

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A solution of FeCl 3 when treated with K 4 Fe ( CN ) 6 gives a prussian blue precipitate due to the formation of

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Highest oxidation state of Mn is exhibited in Mn 2 O 7 . The correct statements about Mn 2 O 7 are (A) Mn is tetrahedrally surrounded by oxygen atoms (B) Mn is octahedrally surroun

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Which of the following elements have half-filled f-orbitals in their ground state ? (Given : atomic number Sm - 62 ; Eu = 63 ; Tb = 65 ; Gd = 64 , Pm = 61 ) Choose the correct answ

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The correct order of basicity of oxides of vanadium is

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Nd 2 + = _ _ _ _ _ _

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KMnO 4 oxidises I - in acidic and neutral/faintly alkaline solution, respectively to

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During the qualitative analysis of SO 3 2 - using dilute H 2 SO 4 , SO 2 gas is evolved which turns K 2 Cr 2 O 7 solution (acidified with dilute H 2 SO 4 ):

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The number of electrons involved in the reduction of permanganate to manganese dioxide in acidic medium is _____ .

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A solution of CrO 5 in amyl alcohol has a....colour

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The set of correct statements is: (i) Manganese exhibits + 7 oxidation state in its oxide. (ii) Ruthenium and Osmium exhibit + 8 oxidation in their oxides. (iii) Sc shows + 4 oxida

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Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state changes from

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