d- and f-Block Elements PYQs Set 8 (PDF)

Set 8 of 15 · Questions 211-240 of 443

In the print window choose “Save as PDF”. The file prints without a web address or date line.

Mere Teacher · Previous Year Questions JEE Main Chemistry · d- and f-Block Elements · Set 8 (Q211-240)
Scan or visit mereteacher.com for free PYQ practice, timed CBT tests, step-by-step solutions and BroBot AI. Answers and solutions are free with a sign-up.
211. $The element which shows only one oxidation state other than its elemental form is :$ (1) $Cobalt$ (2) $Titanium$ (3) $Nickel$ (4) $Scandium$ 212. $Choose the correct option having all the elements with d^{10} electronic configuration from the following:$ (1) $^{27} Co,^{28} Ni,^{26} Fe,^{24} Cr$ (2) $^{29} Cu,^{30} Zn,^{48} Cd,^{47} Ag$ (3) $^{46} Pd,^{28} Ni,^{26} Fe,_{2}^{24} Cr$ (4) $^{28} Ni,^{24} Cr,^{26} Fe,^{29} Cu$ 213. $Gadolinium has a low value of third ionisation enthalpy because of$ (1) $High basic character$ (2) $Small size$ (3) $High exchange enthalpy$ (4) $Hight electronegativity$ 214. $Identify a 'Chemical twin' among the following:$ (1) $Zr - Ta$ (2) $Nb - Tc$ (3) $Hf-Re$ (4) $Nb - Ta$ 215. $The electronic configuration of transition elements is exhibited by$ (1) $n s^{1}$ (2) $n s^{2} n p^{5}$ (3) $n s_{(}^{2} n - 1_{)} d^{1 - 10}$ (4) $n s_{(}^{2} n - 1_{)} d^{10}$ 216. $Which among the following cations produces colourless aqueous solution in their respective oxidation state?$ (1) $Ti^{3 +}$ (2) $V^{3 +}$ (3) $Sc^{3 +}$ (4) $Cu^{2 +}$ 217. $The lanthanoid that does NOT show +4 oxidation state is$ (1) $Tb$ (2) $Dy$ (3) $Ce$ (4) $Eu$ 218. $The correct order of basicity of oxides of vanadium is$ (1) $V_{2} O_{3} > V_{2} O_{4} > V_{2} O_{5}$ (2) $V_{2} O_{3} > V_{2} O_{5} > V_{2} O_{4}$ (3) $V_{2} O_{5} > V_{2} O_{4} > V_{2} O_{3}$ (4) $V_{2} O_{4} > V_{2} O_{3} > V_{2} O_{5}$ 219. $From the list given below, the number of lanthanides which exhibit +4 state in their oxides is Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy$ (1) $5$ (2) $4$ (3) $6$ (4) $2$ 220. $In the neutral or faintly alkaline medium, KMnO_{4} oxidises iodide into iodate. The change in oxidation state of manganese in this reaction is from$ (1) $+6 to +5$ (2) $+7 to +4$ (3) $+6 to +4$ (4) $+7 to +3$ 221. $Iron (III) catalyses the reaction between iodide and persulphate ions, in which A. Fe^{3 +} oxidises the iodide ion B. Fe^{3 +} oxidises the persulphate ion C. Fe^{2 +} reduces the iodide ion D. Fe^{2 +} reduces the persulphate ion Choose the most appropriate answer from the options given below:$ (1) $B only$ (2) $A only$ (3) $B and C only$ (4) $A and D only$ 222. $Give below are two statements: Statement I : The higher oxidation states are more stable down the group among transition elements unlike p block elements. Statement II : Copper can not liberate hydrogen from weak acids. In the light of the above statements, choose the correct answer from the options given below :$ (1) $Both Statement I and Statement II are true$ (2) $Statement I is false but Statement II is true$ (3) $Both Statement I and Statement II are false$ (4) $Statement I is true but Statement II is false$ 223. $All Cu (II) halides are known, except iodide, the reason for it is that$ (1) $Cu^{2 +} has much more negative hydration enthalpy$ (2) $Cu^{2 +} ion has smaller size$ (3) $iodide is bulky ion$ (4) $Cu^{2 +} oxidises iodide to iodine.$ 224. $The order of melting points of Cr, Mo and W is$ (1) $Cr > Mo > W$ (2) $Mo > Cr > W$ (3) $W > Mo > Cr$ (4) $W > Cr > Mo$ 225. $Among V, Cr, Zn, Fe, the metal having lowest enthalpy of atomization is$ (1) $V$ (2) $Cr$ (3) $Zn$ (4) $Fe$ 226. $Given below are two statements: Statement I : Potassium permanganate on heating at 573 K forms potassium manganate. Statement II : Both potassium permanganate and potassium manganate are tetrahedral and paramagnetic innature. choose the most appropriate answer from the options given below:$ (1) $Statement I is true but statement II is false$ (2) $Both statement I and statement II are true$ (3) $Statement I is false but statement II is true$ (4) $Both statement I and statement II are false$ 227. $Pair of transition metal ions having the same number of unpaired electrons is$ (1) $Ti^{3 +}, Mn^{2 +}$ (2) $Ti^{2 +}, Co^{2 +}$ (3) $Fe^{3 +}, Cr^{2 +}$ (4) $V^{2 +}, Co^{2 +}$ 228. $What is the effect of lanthanoid contraction in lanthanoid series of elements with increasing atomic number?$ (1) $Decreases in atomic radii$ (2) $Increases in atomic radii$ (3) $Decreases in melting point$ (4) $Increases in melting point$ 229. $The pair of compounds having metals in their highest oxidation state is :$ (1) $M n O_{2}, F e C l_{3}$ (2) $[M n O_{4}]^{-}, C r O_{2} C l_{2}$ (3) $[Fe(CN)_{6}]^{2-}, [Co(CN)_{6}]^{3-}$ (4) $[N i C l_{4}]^{2-}, [Ni (C O)_{4}].$ 230. $The compound with more covalent character in the following is$ (1) $FeF_{3}$ (2) $VF_{5}$ (3) $VF_{2}$ (4) $TiF_{2}$ 231. $Which of the following is Baeyer's reagent?$ (1) $alkaline KMnO_{4}$ (2) $alkaline Na_{2} Cr_{2} O_{7}$ (3) $acidic K_{2} Cr_{2} O_{7}$ (4) $MnO_{2}$ 232. $K_{2} C r_{2} O_{7} paper acidified with dilute H_{2} S O_{4} turns green when exposed to$ (1) $Carbon dioxide$ (2) $Sulphur trioxide$ (3) $Hydrogen sulphide$ (4) $Sulphur dioxide$ 233. $The first transition series metal ' M' has the highest enthalpy of atomisation in its series. One of its aquated ion (M^{n +}) exists in green colour. The nature of the oxide formed by the above M^{n +} ion is:$ (1) $basic$ (2) $neutral$ (3) $amphoteric$ (4) $acidic$ 234. $On heating potassium permanganate, one of the following compound is not obtained$ (1) $MnO$ (2) $K_{2} MnO_{4}$ (3) $O_{2}$ (4) $MnO_{2}$ 235. $Which of the following acts as a strong reducing agent? (Atomic number : Ce = 58, Eu = 63, Gd = 64, Lu = 71)$ (1) $Lu^{3 +}$ (2) $Gd^{3 +}$ (3) $Eu^{2 +}$ (4) $Ce^{4 +}$ 236. $Which of the following ions can reduce dilute acid to give hydrogen gas?$ (1) $Ti^{2 +}, Cr^{2 +}$ (2) $Mn^{3 +}, Ti^{2 +}$ (3) $Mn^{3 +}, Cr^{2 +}$ (4) $Co^{3 +}, Cr^{2 +}$ 237. $Assertion (A): In general, transition metals have high melting points. Reason (R): More number of electrons from '(n - 1)d' and ' ns ' are involved in interatomic metallic bonding.The correct option among the following is$ (1) $(A) is true, (R) is true and (R) is the correct explanation for (A)$ (2) $(A) is true, (R) is true but (R) is not the correct explanation for (A)$ (3) $(A) is true but (R) is false$ (4) $(A) is false but (R) is true$ 238. $Aqueous sulphite reacts with dilute sulphuric acid to form X (g) . The liberated X (g) is passed into acidified KMnO_{4} solution. What is the oxidation state of Mn in the product formed?$ (1) $+6$ (2) $+4$ (3) $+2$ (4) $+3$ 239. $The correct decreasing order of spin only magnetic moment values (BM) of Cu^{+}, Cu^{2 +}, Cr^{2 +} and Cr^{3 +} ions is:$ (1) $Cr^{3 +} > Cr^{2 +} > Cu^{+} > Cu^{2 +}$ (2) $Cu^{+} > Cu^{2 +} > Cr^{3 +} > Cr^{2 +}$ (3) $Cr^{2 +} > Cr^{3 +} > Cu^{2 +} > Cu^{+}$ (4) $Cu^{2 +} > Cu^{+} > Cr^{2 +} > Cr^{3 +}$ 240. $M n_{2} (CO)_{10} is an organometallic compound due to the presence of :$ (1) $Mn- C bond$ (2) $Mn- Mn bond$ (3) $Mn- O bond$ (4) $C- O bond$