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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.
| 151. |
What are interstitial compounds ? |
| Answer» Interstitial compounds are non-stichiometric compounds which are formed when non- metals like H, C, N etc., are heated with transition elements. In these compounds the non-metal atoms occpy the interstitial species of metal atoms. Ex : `TiH_(0.54)` | |
| 152. |
Write the characteristics of interstitial compounds. |
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Answer» Characteristics of interstitial compounds : `rarr` These are non stoichiometric and are neither typically ionic nor covalent. `rarr` They have high melting points, higher than of pure metals. `rarr` They are very hard, some borides approach diamond in hardness. `rarr` They retain metallic conductivity. `rarr` They are chemically inert. |
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| 153. |
Among the first transition series (3d series) Chromium has highest melting point. Why? |
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Answer» Among first transition series (3d-series) chromium has highest melting point. Reason : In chromium one unpaired electron per d-orbital is particularly favourable for strong inter atomic interactions. |
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| 154. |
Why do transition elements exhibits characteristic properties ? |
| Answer» Due to the presence of partially filled d-orbitals transition elements exhibit characteristic properties such as variable oxidation states, colour property, magnetic property, complex tendency etc | |
| 155. |
Wtite the characteristic properties of transition elements. |
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Answer» Transition elements exhibits typical characteristic properties. `rarr` Electronic configurations. `rarr` Variable oxidation states. `rarr` Para and ferro magnetic properties. `rarr` Formation of coloured hydrated ions. `rarr` Alloy forming ability. `rarr` Catalytic property. `rarr` Complex forming ability. `rarr` Metallic character. `rarr` Interstitial compounds. |
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| 156. |
Write the characteristic properties of transition elements. |
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Answer» `rarr` Electronic configurations. `rarr` Variable oxidation states. `rarr` Para and ferro magnetic properties. `rarr` Formation of coloured hydrated ions. `rarr` Alloy forming ability. `rarr` Catalytic property. `rarr` Complex forming ability. `rarr` Metallic character. `rarr` Interstitial compounds. |
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| 157. |
Write the electronic configuration of chromium (Cr) and copper (Cu). |
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Answer» `rarr` Electronic configuration of chromium (Cr) `-[Ar]4s^(1)3d^(5)`. `rarr` Electronic configuration of copper (Cu) `-[Ar]4s^(1)3d^(10)`. |
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| 158. |
Write down the electronic configuration of `Cr^(3+)` |
| Answer» `Cr^(3+)` electronic configuration is `[Ar]4s^(0)3d^(3)` | |
| 159. |
Write the electronic configuration of `Co^(2+) and Mn^(2+)`. |
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Answer» `rarr` The electronic configuration of `Co^(+2)" is "[Ar] 4s^(0) 3d^(7)`. `rarr` The electronic configuration of `Mn^(+2)" is "[Ar] 4s^(0) 3d^(5)`. |
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| 160. |
Why are d-block elements called transition elements ? |
| Answer» The name transition elements given to d-block is due to their properties which are transitioned between the electropositive s-block metals and electronegative p-block elements. | |
| 161. |
In what way is the electronic configuration of transition elements different from non transition elements ? |
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Answer» `rarr` The general electronic configuration of transition elements is `(n-1)d^(1-10)ns^(1-2)` `rarr` The general electronic configuration of non-transition elements is `(n-1)d^(10)ns^(2)` |
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| 162. |
Write down the electronic configuration of `Co^(2+)` |
| Answer» `Co^(2+)` electronic configuration is `[Ar]4s^(0)3d^(7)` | |
| 163. |
Write the general electronic configuration of transition elements. |
| Answer» General electronic cOnfiguration of transition elements is `(n - 1)d^(1-10) ns^(1-2)`. | |
| 164. |
The lightest transition element isA. HgB. ScC. FeD. Ti |
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Answer» Correct Answer - B Sc (21) - first element of all d-block is lighest |
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| 165. |
General electron configuration of transition elements isA. `(n-1) d^(1-10) ns^(0//1//2)`B. `(n+1) d^(1-10) ns^(0//1//2)`C. `(n-1) d^(0-10) ns^(1//2)`D. `(n-1) d^(1-10) ns^0` |
| Answer» Correct Answer - A | |
| 166. |
The number of transition series in the periodic table areA. 10B. 20C. 40D. 60 |
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Answer» Correct Answer - C 40, 3d series-10, 4d series -10, 5d series -10, 6d series -10. |
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| 167. |
The number of transition series in the periodic table areA. 20B. 28C. 30D. 40 |
| Answer» Correct Answer - D | |
| 168. |
The lightest transition element isA. HgB. Sc, Y, LaC. FeD. Ti |
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Answer» Correct Answer - B The first transition element Sc is lightest. |
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| 169. |
The number of transition series in the periodic table areA. 4B. 3C. 5D. 2 |
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Answer» Correct Answer - A `3d,4d,5d` and 6d series. |
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| 170. |
The number of incomplete shells in transition elements areA. 3B. zeroC. 2D. 1 |
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Answer» Correct Answer - C Last and second last shells are incompletely filled |
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| 171. |
In which of the following actinoid elements, 6d sub-shells is vacant?A. PaB. NpC. LrD. Pu |
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Answer» Correct Answer - D `Pu(Z=94)[Rn]5f^(6)7s^(2)` |
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| 172. |
The no. of incomplete shell in f - block element isA. 2B. 1C. 0D. 3 |
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Answer» Correct Answer - D (n-2) f, (n-1) d and ns orbitals |
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| 173. |
Total number of transuranic elements present in periodic table are `A. 11B. 25C. 29D. 20 |
| Answer» Correct Answer - B | |
| 174. |
From La to Lu ionisation potentialA. decreasesB. increasesC. constantD. first increases than decreases |
| Answer» Correct Answer - B | |
| 175. |
The number of incomplete shells in transition elements are |
| Answer» Correct Answer - D | |
| 176. |
First transuranium element isA. NpB. UupC. UuoD. Uut |
| Answer» Correct Answer - A | |
| 177. |
All actinides areA. methalloidB. inertC. radioactiveD. nonradioactive |
| Answer» Correct Answer - C | |
| 178. |
Transuranium elements areA. heavier than uraniumB. lighter than uraniumC. have lesser atomic no. than uraniumD. have same atomic no. as that of uranium |
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Answer» Correct Answer - A Transuranium elements are heavier than uranium as they have their atomic number ( gt 92 ) and mass number more than that of uranium |
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| 179. |
In actinides incoming electron enters intoA. 4f-orbitalB. 5f-orbitalC. 3f-orbitalD. 6f-orbital |
| Answer» Correct Answer - B | |
| 180. |
Synthetic radioactive elements present in actinides areA. 9B. 10C. 11D. 12 |
| Answer» Correct Answer - C | |
| 181. |
Which of the following belong to actinide series ?A. NdB. UC. SmD. Au |
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Answer» Correct Answer - B U (92) belongs to 5f series (Actinides) |
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| 182. |
Which of the following belong to actinide series ?A. CmB. LaC. LuD. Gd |
| Answer» Correct Answer - A | |
| 183. |
Naturatl rasioctive elements of actinide series areA. up to thoriumB. up to uraniumC. up a curiumD. up to protactium |
| Answer» Correct Answer - B | |
| 184. |
Which of the following element belong to actinide series ?A. LaB. LuC. GdD. Th |
| Answer» Correct Answer - D | |
| 185. |
Which of the following elements belong to actinoid series?A. CeriumB. LutetiumC. ThoriumD. lanthanum |
| Answer» Correct Answer - C | |
| 186. |
Which of the following does not belong to 3d series of transition elements?A. TitaniumB. IronC. PalladiumD. Vanadium |
| Answer» Correct Answer - c | |
| 187. |
Which out of the following belong to 3d-series?A. CopperB. CobaltC. GoldD. Silver |
| Answer» Correct Answer - a,b | |
| 188. |
In the periodic table actinons belong toA. 6th period group 4B. 6th period group 3C. 7th period group 3D. 7th period group 4 |
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Answer» Correct Answer - C Actinides -`[Rn] 5f^(1-14) 6d^(0-1) 7s^2` `therefore` Period - 7, Group -3 |
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| 189. |
The individual members of the actinide series is called asA. actinoidB. actinonC. 2nd inner transition elementD. all of these |
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Answer» Correct Answer - D All three names . |
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| 190. |
The electronic configurationo of Cu(II) is `3d^(9)` whereas that of Cu(I) is `3d^(10)`. Which of the following is correct ?A. `Cu^(2+)` is more stable than `Cu^(+)`B. `Cu^(2+)` is less stable than `Cu^(+)`C. `Cu^(2+)` and `Cu^(+)` ions are equally stableD. stabllity of `Cu^(+)` and `Cu^(2+)` depends on the nature of copper salts |
| Answer» Correct Answer - A | |
| 191. |
The electronic configurationo of Cu(II) is `3d^(9)` whereas that of Cu(I) is `3d^(10)`. Which of the following is correct ?A. Cu(II) is more stableB. Cu(II) is less stableC. Cu(I) and Cu(II) are stableD. Stability of Cu(I) and Cu(II) depends on nature of copper salts . |
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Answer» Correct Answer - A (a) Cu(II) is more stable. In aqueous solution, Cu(I) ion undergoes disproportion into Cu(II) ion and Cu. `2Cu^(+)(aq) to Cu^(2+)(aq)+Cu(s)` |
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| 192. |
The electronic configurationo of Cu(II) is `3d^(9)` whereas that of Cu(I) is `3d^(10)`. Which of the following is correct ?A. Cu(II) is more stableB. Cu(II) is less stableC. Cu(I) and Cu(II) are equally stableD. Stability of Cu(I) and Cu(II) depends on nature of copper salts |
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Answer» Correct Answer - A Cu(II) is more stable than Cu(I). As it is known that, Cu(I) has `3d^(10)` stable configuration while Cu(II) has `3d^(9)` configuration. But Cu(II) is more stable due to greater effective nuclear charge of Cu(II) i.e., it hold 17 electrons instead of 18 in cu(I). |
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| 193. |
The `Cu^(2)` having `3d^(9)` congiguration,` Cu^(+)` having `3d^(10)` configuration. The `Cu^(2+)` is ,A. is more stableB. is less stableC. is equally stableD. stability depends upon the nature of copper salt |
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Answer» Correct Answer - B `Cu^(+)` has `d^(10)` configuration and `Cu^(2+)` has `d^(9)` configuration. Hence `Cu^(2+)` is less stable than `Cu^(+).` |
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| 194. |
Transition metal exhibits an oxidation state grater than `+2` due to loss ofA. p-electronB. s and p-electronsC. p and d-electronsD. s and d-electrons |
| Answer» Correct Answer - D | |
| 195. |
On the basis of lanthanoid contraction, explain the following: (i) Nature of bonding in `La_(2)O_(3)` and `Lu_(2)O_(3)`. (ii) Trends in the stability of oxo salts of lanthanoids from La to Lu. (iii) Stability of the complexes of lanthanoids. (iv) Radii of 4d and 5d block elements. (v) Trends in acidic character of lanthanoids oxides. |
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Answer» (a) `La_(2)O_(3)` is expected to be ionic in nature because the element La is present in group 3 (d-block). The element Lu is the last member of lanthanoid family. Since the atomic size decreases along period, its compound `Lu_(2)O_(3)` is expected to be covalent in nature. (ii) Sice the atomic size decreases from La to Lu in the family of lanthanoids, the oxo salts tar expecte to a more and more covalent character. The stability of these salts is expected to decrease . (iii) With the decrease in the atomic size or atomic radius along lanthanoids, the bonding beteeen the metal atom ( or ion ) and hte ligands is expected to become stronger. The stability of the complexes is therefore, expected to increase. (iv) Atomic radius of the element belonging to 4d and 5d series but presenet in the same group are expected to the similar due to lanthanoid contraction. (v) The oxides of the lanthanoid family `M_(2)O_(3)` dissolve in water to form `M(OH)_(3)`. Due to gradual decrease in the size of `M^(3+)` ion, there is an increase in covalent character of M-OH bond. The cleavage of O-H bond becomes easy and the acidic character of the lanthanoid oxides is expected to increase from left to right. |
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| 196. |
Which elements have low ionisation enthalpy as compare to their neighbour element in first transition series?A. Cr, CuB. Cr, ZnC. Cr, MnD. Cu, Zu |
| Answer» Correct Answer - A | |
| 197. |
The electronic configuration of Cu(II) is`3d^(9)` whereas that of Cu(I) is `3d^(10)` .Which of the following is correct ?A. Cu (II) is more stableB. Cu(II) is less stableC. Cu(I) and Cu(II) are equally stable.D. Stability of Cu(I) and Cu(II) depends on nature of copper salts. |
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Answer» Correct Answer - a Though Cu(I) has `3d^(10)` stable configuration while Cu(II) has `3d^(9)` configuration , yet Cu(II) is more stable due to greater effective nuclear energy charge of Cu(II) ( i.e., to hold 17 electrons instead of 18 in Cu(I). |
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| 198. |
Answer the following questions (i) Which element of the first transition series has highest second ionisation enthalpy? (ii) Which element of the first transition series has highest third ionisation enthalpy? (iii) Which element of the first transition series has lowest enthalpy of atomisation? (b) Identify the metal and justify your answer. (i) Carbonyl `M(CO)_(5)` (ii) `MO_(3)F` |
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Answer» (i) The element copper (Cu) has the highest value of `Delta_(i)H_(2)` (1958 kJ `mol^(-1)`) because after losing 4s electron ( `3d^(10)4s^(1)` configuration ), `Cu^(+)` in acquires a stable electronic configuration. The release of the second electron from the ion is quite difficult. (ii) The element zinc (Zn) has the highest value of `Delta_(i)H_(3)`(3826 kJ `mol^(-1)`). Its electronic configuration is `3d^(10)4s^(2)`. After losing two electrons, `Zn^(2+)(3d^(10))` acquire a stable configuration. The release of the third electron from the filled orbital is extremely difficult. (iii) The element zinc (Zn) has the lowest value of enthalpy of atomisation (126 kJ `mol^(-1)`) because of the absence of any unpaired electron in its atom. Therefore, the metallic bonds in the crystal lattice are quite weak. It has, therefore, least enthalpy of atomisation value. |
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| 199. |
Copper exhibits only +2 oxidation state in its stable compounds. Why?A. Coppper is a transition metal in +2 stateB. `+` 2 state compounds of copper are formed by exothermic reactionsC. 2D. 2 |
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Answer» Correct Answer - B The stability of `Cu^(2+)`(aq) rather then `Cu^(+)`,(aq) is due to much more negative `Delta_("hyd")H^(@) " of " Cu^(2+)`(aq) than `Cu^(+)`, which compensates for second ionisation enthalpy of Cu. |
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| 200. |
Which of the following has highest ionisation energy ?A. CrB. ZnC. VD. Fe |
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Answer» Correct Answer - B It is due to stable `d ^(10)` configuration. |
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