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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 501. |
Which of the following cannot reduce the acidified solution of permanganate?A. `(COOH)_2`B. `H_2`C. Nascent hydrogenD. `Fe^(2+)` ions |
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Answer» Correct Answer - b `O_2` is not very stro9ng reducing agent. |
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| 502. |
In general the order of reactivity of halogens with transition metals isA. `F_2gtCl_2gtBr_2gtI_2`B. `F_2ltCl_2ltBr_2ltI_2`C. `F_2ltCl_2gtBr_2ltI_2`D. `F_2gtI_2gtBr_2gtCl_2` |
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Answer» Correct Answer - a The reactivity depends upon the En value . Greater is the EN value more is the reactivity. |
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| 503. |
Transition elements form binary compounds with halogens. Which of the following elements will form `MF_(3)` type compounds ?A. CrB. CoC. CuD. Ni |
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Answer» Correct Answer - a,b Cr and Co from `CrF_(3)` and `CoF_(3)`. Cu and Ni donot form `CuF_(3)` and `NiF_(3)` |
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| 504. |
The basic strength `"…................"` as we proceed from`La(OH)_(3)` to `Lu(OH)_(3)` ( decreases or increases or remains constant). |
| Answer» Correct Answer - decreases | |
| 505. |
Calomel is the name ofA. `Hg_(2)Cl_(2)+Hg`B. `HgCl_(2)`C. `Hg+HgCl_(2)`D. `Hg_(2)Cl_(2)` |
| Answer» Correct Answer - D | |
| 506. |
Complete the following `:` `2MnO_(4)^(-) (aq) + 5H_(2)O_(2)(aq) rarr 2Mn^(2+) + 8 H_(2)O+ .....` |
| Answer» `2MnO_(4)^(-)+ 5H_(2)O_(2)(aq)+6H^(+) rarr 2Mn^(2+) + 8 H_(2)O+ 5O_(2)` | |
| 507. |
What is the basic difference between the electronic of transition and inner transitoin elements? |
| Answer» General electronic configuration of transition elements `=`[Noble gas ] `( n -1) d^(1-10) ns^(1-2)` and for inner transition elements `= ( n -2) f^(1-14) d^(0-1) ns^(0-2)`. Thus, in transition elements, last electron enters d-orbital of penultimate shell while in inner transition elements, it enters f-orbital of ante-penultimate shell. | |
| 508. |
Why is `Cu^(+)` ion not stable in aqueous solution ? or Why is `Cu^(+)` is not known in aqueous solution ? |
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Answer» Cu(I) compounds involving `Cu^(+)` ions are unstable in aqueous solution and undergo disproportionation. The stablility of `Cu^(2+)` ions as compared to `Cu^(+)` ion is due to more negative `Delta_(hyd)H^(@)` of `Cu^(2+)(aq)` than that of `Cu^(+)(aq)` which compensates the second ionisation enthalpy of Cu involved in the formation of `Cu^(2+)` ion. `2Cu^(+) to Cu^(2+) +Cu` |
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| 509. |
Explain why `Cu^(+)` ion is not stable in aqueous solution ? |
| Answer» `Cu^(2+)(aq)` is much more stable `Cu^(+)` ( aq). This is because although second ionization enthalpy of copper is large bu `Delta_(hyd)` H for `Cu^(2+) (aq)` is much more negative than that for `Cu^(+)(aq)` and hence it more than compensates for the second ionization enthalpy of copper. Therefore, many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as follows `: 2Cu^(+)rarr Cu^(2+) + Cu`. | |
| 510. |
Which of the following statements is correct?A. Iron belongs to third transition series of the periodic tableB. Iron belongs to `f-`block of the periodic tableC. Iron belongs to first transition seriesD. Iron belongs to group `VIII` of the periodic table |
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Answer» The correct statement is that iron belongs to first transition series of elements. It is called `3d` series. The members of this series are `Se" "Ti" "V" "Cr" "Mn" "Fe" "Co" "Ni" "Cu" "Zn` The electronic confine of `Fe^(26)` is `3d^(6).4s^(2)` |
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| 511. |
Which is a stronger reducing agent `Cr^(2+)` or `Fe^(2+)` and why ? |
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Answer» `Cr^(2+)` is a stronger reducing agent than `Fe^(2+)`. Reason . `E_(Cr^(3+) //Cr^(2+))^(@) `is `-ve ( -0.41V)` whereas `E_(Fe^(3+) //Fe^(2+))^(@)` is `+ve ( + 0.77V)`. Thus, `Cr^(2+)` is easily oxidized to `Fe^(3+)` but `Fe^(2+)` cannot be easily oxidized to `Fe^(3+)` . Hence, `Cr^(2+)` is stronger reducing agent than `Fe^(2+)` |
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| 512. |
The reason for greater range of oxidation states in actinoids is attributed toA. the radioactive number of actinoidsB. actinoid contractionC. 5f,6d and 7s levels having comparable energiesD. 4f and 5d levels being close in energies |
| Answer» The greater range of oxidation states shown by actinoids is due to 5f,6d and 7s levels having comparable energies and thus all their electrons can take part in bond formation. | |
| 513. |
Which of the following statements is not true ?A. An acidified solution of `K_(2) Cr_(2) O_(7)` liberated `I_(2)` from KIB. In acidic medium, dichromate ion is presentC. Neutral `KMnO_(4)` oxidises KI to `I_(2)`D. Potassium dichromate is an oxidising agent |
| Answer» Correct Answer - C | |
| 514. |
How many moles of acidified `FeSO_4` solution can be completely oxidised by one mole of `KMnO_4` ?A. 10B. 5C. 6D. 2 |
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Answer» Correct Answer - B `2KMnO_4 + 3H_2SO_4 to K_2SO_4 + 3MnSO_4 + 3H_2O + 5[O]` `2FeSO_4 + H_2SO_4 + [O] to Fe_2(SO_4)_3 + H_2O xx5` From the above equation , it is clear that 2 moles of `KMnO_4` oxidise 10 moles of `FeSO_4` completely. Hence 1 mole of `KMnO_4` will oxidise 5 moles of `FeSO_4` completely . |
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| 515. |
Faulty statement for paramagnetic ion isA. paramagnetic ions are colouredB. paramagnetic ions are colourlessC. paramagnetic ions contain unpaired electronsD. paramagnetic ions do not show zero magnetic moment |
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Answer» Correct Answer - B Paramagnetic ions contains unpaired `e^-` in d-orbitals , so it leads to d-d transition imparting colour. |
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| 516. |
silver nature is used for making inks and hair dyes. |
| Answer» Correct Answer - True. | |
| 517. |
When copper nitrate is strongly heated, the compound obtained isA. copper nitriteB. copperC. copper nitrideD. copper oxide |
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Answer» Correct Answer - D `2Cu(NO_(3))_(2)overset(Delta)rarr2CuO+4NO_(2)+O_(2)` |
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| 518. |
Hair dye containsA. copper nitrateB. gold chlorideC. silver nitrateD. lead nitrate |
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Answer» Correct Answer - C Hair dye contains silver nitrate. |
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| 519. |
One of the following is diamagneticA. CuB. `Cu^+`C. `Cu^(2+)`D. All the above |
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Answer» Correct Answer - B `Cu^(+) = 3d^10` (zero unpaired electron) is diamagnetic |
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| 520. |
The correct statement(s) from among the following is/are? (i). all the d and f-block elements are metals (ii). all the d and f-block elements form coloured ions (iii). All th d- and f-block elements form paramagnetic ionsA. all the d and f block elements are metalsB. all the d and f block elements form coloured ionsC. all the d and f block elements form paramagnetic ionsD. (a) and (b) both |
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Answer» Correct Answer - A All d and f block elements are metals whereas all d and f block metals may not form coloured ions and paramagnetic |
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| 521. |
The correct statement(s) from among the following is/are? (i). all the d and f-block elements are metals (ii). all the d and f-block elements form coloured ions (iii). All th d- and f-block elements form paramagnetic ionsA. (i) and (ii)B. (ii) and (iii)C. (i) onlyD. (iii) only |
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Answer» Correct Answer - C All d and f block elements are metals but all do not form coloured ion, paramagentic |
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| 522. |
Which of the following is diamagnetic in nature ?A. `MnCl_2`B. `ZnCl_2`C. `CuCl_2`D. `CrCl_3` |
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Answer» Correct Answer - B `ZnCl_2` is diamagnetic in nature as it contains no unpaired electons Zn in `ZnCl_2` is present as `Zn^(+2)` ion `(3d^10 4s^0)` `{:(MnCl_2, Mn^(+2)(3d^5 4s^0)),(CuCl_2,Cu^(+2)(3d^9 4s^0)),(CrCl_3,Cr^(+3)(3d^3 4s^0)):}` |
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| 523. |
Bordeaux mixture consists of lime andA. `FeSO_4`B. `CuSO_4`C. `Cu(NO_3)_2`D. `AgNO_3` |
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Answer» Correct Answer - b Lime`+CuSO_4` is called Bordeaux mixture and is used as fungicide. |
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| 524. |
Which of the following is known as WORM SILVER?A. `AgCl`B. A specific horn,type article made of silverC. `Ag_2S`D. `PbS` containing traces of `Ag_2S` |
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Answer» Correct Answer - a `AgCl` is called Horn silver or Worm silver. `Ag_2S` is called Argentite or silver glance. |
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| 525. |
It is always advisable not to cover egg yolk or mustard with silver cutlery becauseA. Silver reacts with water of egg yolk to form AgOHB. Silver reacts with sulphur of egg yolk forming black `Ag_2S`C. silver reacts with egg yolk forming `Ag_2SO_4` which is a poisonous substance.D. Silver attracts UV light of the atmosphere, thereby spoiling the food. |
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Answer» Correct Answer - b Both egg yolk and mustard contain large quantity of sulphur (as its compounds) which react with Ag. `2Ag+StoAg_2S` (Black colour). |
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| 526. |
Silver halides are used in photography because they areA. PhotosensitiveB. Soluble in hyposolutionC. Soluble in `NH_4OH`D. Insoluble in acids |
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Answer» Correct Answer - a Silver halides are used in photography because they are photosensitive in nature and on exposure to light, they are easily reduced to etallic silver by mild reducing agents like hydroquinone, ferrous oxalate etc. |
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| 527. |
What is an alloy ? Give example. |
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Answer» Alloy : An intimate mixture having physcial properties similar to that of the metal formed by a metal with other metals or metalloids or sometimes a non metal is called as an alloy. Eg. : Invar `-64%" Fe "35%" Ni, "` Mn 8cc in iraces Nichrome `-60% Ni, 25% Fe, 15% Cr. |
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| 528. |
Why do the transition metals readily form alloys ? |
| Answer» Because of similar atomic or ionic radii and similar characterstic properties of transition elements alloys are readily formed by these elements. | |
| 529. |
Which of the following statement is incorrect for pair of elements Zr-Hf ?A. Both possess same number of valence electronsB. Both have identical atomic sizesC. Both have almost identical ionic radiiD. Both of these belong to same period of periodic table |
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Answer» Correct Answer - D Zr - Hf are chemical twins and are present in period 5th and 6th respectively. |
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| 530. |
Which one of the following is not oxidized by acidified `KMnO_4` ?A. Sodium oxalateB. Potassium iodideC. Ferrous sulphateD. Sodium sulphate |
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Answer» Correct Answer - D Sodium sulphite is oxidised to sodium sulphate `Na_2SO_3 + [O] to Na_2SO_4 (2KMnO_4 + 3H_2SO_4 to K_2SO_4 + 2MnSO_4 + 3H_2O + 5 [O])` |
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| 531. |
The mineral from which potassium permanganate is manufactured isA. Pyrolusire , `MnO_2`B. Braunite , `Mn_2O_3`C. Hausmannite `Mn_3O_4`D. Manganite , `Mn_2O_3 . H_2O` |
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Answer» Correct Answer - A `KMnO_4` is prepared from pyrolusite ore `(MnO_2)` |
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| 532. |
When an ecidified solution of ferrous sulphiate is treated with potassium paramagnet solution, the ion which is oxidised isA. `MnO_(4)^(-)`B. `NH_(4)^(+)`C. `Fe ^(3+)`D. `SO_(4)^(2-)` |
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Answer» Correct Answer - C `Fe ^(2+)overset("oxidises")toFe^(3+)` |
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| 533. |
For the redox reaction, `MnO_(4)^(-) + C_(2)O_(4)^(2-) + H^(+) rarr Mn^(2+) + CO_(2) + H_(2)O` the correct coefficients of the reactants for the balanced reaction areA. `{:(MnO _(4)^(-), C_(2)O_(4)^(2-), H^(+)), (2,5,16):}`B. `{:(MnO _(4)^(-), C_(2)O_(4)^(2-), H^(+)), (6,5,2):}`C. `{:(MnO _(4)^(-), C_(2)O_(4)^(2-), H^(+)), (5,16,2):}`D. `{:(MnO _(4)^(-), C_(2)O_(4)^(2-), H^(+)), (2,16,5):}` |
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Answer» Correct Answer - A `MnO_(4)^(-)+8H^(+)+5e^(-) to Mn^(2+)+4H_(2)O]xx2` `{:(COOH),(|),(COOH):}to 2CO _(2)+ 2H^(+)+2e ^(-)]xx5` `{:(" "COOH),(2MnO_(4)^(-)" "+5| +6h^(+) to),(" "COOH):}` `2Mn^(2+) +10CO_(2)+8H_(2)O` |
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| 534. |
The equivalent weight of`KMnO_(4)` (formula weight M) when it is used as an oxidant in neural medium isA. MB. `M/2`C. `M/3`D. `M/5` |
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Answer» Correct Answer - C In neutral medium `MnO_4^(-) + 2H_2O + 3e^(-) to MnO_2 + 4OH^(-)` `therefore `Equivalent weight is `"Molecular weight"/3` |
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| 535. |
Which of the statements (s) is/are not true?A. On passing `H_(2)S`through acidifid `K_(2)Cr_(2)O_(7)`solution, a milky colour is obsevedB. `Na_(2)Cr_(2)O_(7)` is preferred over `K_(2)Cr_(2)O_(7)` in volumetric analysisC. `K_(2)Cr_(2)O_(7)` solution in acidic medium is orengeD. `K_(2)Cr_(2)O_(7)`solution becomes yellow on increasing the pH beyond 7 |
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Answer» Correct Answer - B Being Hygroscopic, sodium dichromate , `Na_(2)Cr_(2)O_(7)` cannot ne used in volumetric analyasis. All other given statements are true. |
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| 536. |
Which of the following paires have same radii?A. Am and CmB. U and NpC. BK and CfD. Pu and Th |
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Answer» Correct Answer - C [U and Np, Pu and Th] Each of these pair has similar radii. |
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| 537. |
In which of the following paris, both ions are coloured in aqueous solution?A. `Ni^(2+),Ti^(4+)`B. `Ni^(2+),Ti^(3+)`C. `Sc^(3+),Ti^(3+)`D. `Cr^(2+),Zn^(2+)` |
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Answer» Correct Answer - B `Ni^(2+)(Z=28)=[AR |
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| 538. |
Oxidation state if iron in ferric isA. `+2`B. `+5`C. `+3`D. `+6` |
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Answer» Correct Answer - C It is the correct answer. |
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| 539. |
How many germs of `K_(2)C_(7)O_(7)` are required to oxidise 20.0g of `Fe^(+)` ion in `FeSO_(4) "to" Fe^(3+)` ions if the reaction is carried out in the acidic medium? Molar mass of `K_(2)Cr_(2)O_(7)` and `FeSO_(4)` are 294 and 152 respectively.A. 6.45gB. 7.45gC. 8.45gD. 9.45g |
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Answer» Correct Answer - A Number of moles of `FeSO_(4)=((20g))/(152g mol^(-1))` =0.132mol Ionic equation for the oxidation reaction carried in the acidic medium may be written as: `Cr_(2)O_(7)^(2-)+6Fe^(2+)+14H^(+) to 2Cr^(3+)+6fe^(3+)+7H_(2)O` 6 mol. of `Fe^(2+) -= ` 1 mol of `K_(2)Cr_(2)O_(7)` 0.132 mol of `Fe^(2+)-=((1 mol))/((6 mol))xx(0.132 mol^(-1)` = 0.022 mol . of `K_(2)Cr_(2)O_(7)` Mass of `K_(2)Cr_(2)O_(7) = (0.022 mol) xx(294 g mol ^(-1))` = 6.468 g. |
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| 540. |
`underset(("bot"))(Cu+conc.HNO_(3))toCu(NO_(3))_(2)+X` (oxide of nitrogen) then X is:A. `N_(2)O`B. `NO_(2)`C. `NO`D. `N_(2)O_(3)` |
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Answer» Correct Answer - B `2 conc. HNO_(3) to 2H_(2)O+2NO_(2)+[O]` `Cu+2HNO_(3) to Cu(NO_(3))_(2)+2[H]` `2[H]+[O]to2H_(2)O` |
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| 541. |
How would you account for the increasing oxidising power in the series `VO_2^(o+)ltCr_2O_7^(2-)MnO_4^(ɵ)`? |
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Answer» This is due to the increasing stabil,ity of the lower species to which they are reduced. (i). `Mn^(VII)O_4^(ɵ)` is reduced to more stable configuration `Mn^(2+)(3d^5)` and `Mn^(4+)(3d^3` or `t_(2g)^3)`. Hence, it acts as strongest oxidising agent amongst the given ions. (ii). `Cr_2^(VII)O_7^(2-)` is reduced to a stable configuration `Cr^(3+)(3d^3` or `t_(2g)^(3))`. Hence it acts as a stronger oxidising agent. (iii). In `(V^VO_2)^(o+)` , V is in `+5` O.S having `3d^0` stable configuration and is therefore not reduced effectively. Thus, the increasing oxidising power is as follows: `VO_2^(o+)ltCr_2O_7^(2-)ltMnO_4^(ɵ)` |
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| 542. |
In context with the transition elements, which of the following statements is incorrect ?A. In the highest oxidation states, the transition metal show basic character and form cationic complexesB. In the highest oxidation states of the first five transitio elements (Sc to Mn), all the 4s and 3d electrons are used for bondingC. Once the d^(5) configuration is exceeded, the tendency to involve all the the 3d electrons in bonding decreases.D. In addition to the normal oxidation states, the zero oxidation state is also show by these element in complexes |
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Answer» Correct Answer - A In the highest oxidation states, the transition metal shows acidic character. |
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| 543. |
In context with the transition elements, which of the following statements is incorrect ?A. In the gighest oxidation states, the transition metal show basic character and form cationic complexesB. In the highest oxidation states of the first five transition elements (Sc to Mn), all the 4s and 3d electrons are used for bondingC. Once the `d^(5)` configuration is exceeded, the tendency to involve all the 3d electrons in bonding decreasesD. In addition to the normal oxidation states, the zero oxidation state is also shown by these elements in complexes |
| Answer» Correct Answer - A | |
| 544. |
Which of the following element about transition elements is incorrect ?A. They show variable oxidation statesB. All the ions are colouredC. They exhibit diamagnetic and paramagnetic propertiesD. They exhiibit catalytic property |
| Answer» Correct Answer - b | |
| 545. |
The incorrect statement for transition elements isA. the last electron of these elements enters in d-orbitalB. the common oxidation state of these elements is +2C. the properties of these elements is intermediate between s- and p-block elementsD. the transition elements with smaller atomic radii is scandium |
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Answer» Correct Answer - D Scandium is the first element of 3d series and possesses largest atomic radii because atomic radii decrease on moving along the period. |
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| 546. |
All lanthanides exhibit a stable valency ofA. 2B. 3C. 4D. 6 |
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Answer» Correct Answer - B We know that all lanthanide shows stable valency of 3. It is due to stability of 4f orbitals, high I. P., high lattie energy of solid, high hydration energy of `Ln^(3+)` ion in aqueous medium and high negative value of reduction potential. |
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| 547. |
Zinc does not exhibit variable valency due toA. presence of complete filled d-orbitalsB. inert pair effectC. presence of 4s-orbitalD. None of the above |
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Answer» Correct Answer - A Zinc contains completely filled d-orbitals and exhibit stable electronic configuration, therefore it does not easily lose their electrons and hence, does not exhibit variable valency. |
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| 548. |
There are two ores `(A_(1))` and `(A_(2))` of metal ( M ). When ore `(A_(1))` is calcined, a black solid (S) is obtained along with liberation of `CO_(2)` and water . The ore `(A_(1))` on treatment with HCl and KI gives a precipitate (P) and ioidine is liberated . The ore `(A_(2))` on roasting gives a gas (G) and metal (M) is set free. When gas (G) is passed through acidified `K_(2)Cr_(2)O_(7)` solution, it turns green. Identify `(M), (A_(1)), (A_(2)), (S),(P)` and `(G)`. |
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Answer» Metal ( M) is Cur and its two ores are `:` `(A_(1)) = ` malachite, `CuCO_(3) . Cu(OH)_(2)`, `(A_(2)) = ` copper glance, `Cu_(2) S` The reactions involved are `underset((A_(1)))(CuCO_(3). Cu(OH)_(2)) overset("Calcination")(rarr) underset("(S) black copper (II) oxide")(2CuO) + COuarr + H_(2)O` `CuCO_(3). Cu(OH)_(2) + 4HCl rarr 2CuCl_(2)+ CO_(2) uarr + 3H_(2)O` `2CuCl_(2)+ 4KI rarr underset("Cuprous iodide ( ppt.)") underset((P))(Cu_(2)I_(2)) + 4KCl + I_(2) uarr` `underset((A_(2))) (2Cu_(2)S) + 3O_(2)overset("Roasting ")(rarr) 2Cu_(2)O+ underset((G))(2SO_(2))` `Cu_(2)S + 2Cu_(2)O rarr underset((M))(6Cu) + SO_(2)` `K_(2)Cr_(2)O_(7) + H_(2)SO_(4) + 3SO_(2) rarrK_(2)SO_(4) + underset("(Green)") (Cr_(2)(SO_(4))_(3)) + 4H_(2)O` `:. M = Cu , (A_(1))= CuCO_(3). Cu(OH)_(2), (A_(2)) = Cu_(2)S, S= CuO, P = Cu_(2)I_(2), G= SO_(2)` |
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| 549. |
`CrO_(3)` is `a//an"….."`A. Acidic oxideB. Basic oxideC. Neutral oxideD. Amphoteric |
| Answer» Correct Answer - A::B | |
| 550. |
Which of the following is expected to have lowest magnetic moment-A. `Ti^(2+)`B. `Mn^(2+)`C. `Co^(2+)`D. `Cu^(2+)` |
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Answer» Correct Answer - D `{:(Ti^(+2)=2"unpaired"),(Mn^(+2)to5"unpaired"),(Co^(+2)to3"unpaired"),(Cu^(+2)to1 "unpaired"):}` |
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