Previous year questions with solutions · 2024 – 2026
| Year | Questions | Papers | Avg / paper | Weightage |
|---|---|---|---|---|
| 2026 | 24 | 19 | 1.3 | 5.05% ▼ 4% vs last year |
| 2025 | 25 | 19 | 1.3 | 5.26% ▼ 28.2% vs last year |
| 2024 | 44 | 20 | 2.2 | 7.33% |
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, Zn = 30, Yb = 70, Sc = 21, La = 57, Gd = 64, Lu = 71, Ti = 22, Ce = 58)
Among the following oxides of 3d elements, the number of mixed oxides are . Ti2O3, V2O4, Cr2O3, Mn3O4, Fe3O4, Fe2O3, Co3O4
Consider the following reactions : NaCl + K2Cr2O7 + H2SO4 A + KHSO4 + NaHSO4 + H2O A + NaOH B + NaCl + H2O B + H2SO4 + H2O2 C + Na2SO4 + H2O In the product 'C', 'X' is the number of O22- units, 'Y' is the total number of oxygen atoms present and 'Z' is the oxidation state of Cr. The value of X + Y + Z is .
KMnO4 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 present in the brown red precipitate formed at the end of the acetate ion test with neutral ferric chloride. The value of X + Y is .
Consider the following reactions A + Little amountNaCl + H2SO4 CrO2Cl2 + Side Products CrO2Cl2(Vapour) + NaOH B + NaCl + H2O B + H+ C + H2O The number of terminal 'O' present in the compound 'C' is
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 (in nearest integer).
The spin-only magnetic moment value of Mn+ ion formed among Ni, Zn, Mn and Cu that has the least enthalpy of atomisation is . (in nearest integer) Here n is equal to the number of diamagnetic complexes among K2[NiCl4], [Zn(H2O)6]Cl2, K3[Mn(CN)6] and [Cu(PPh3)3I]
The molar mass of the water insoluble product formed from the fusion of chromite ore (FeCr2O4) with Na2CO3 in presence of O2 is g mol-1.
The spin only magnetic moment ( ) value (B.M.) of the compound with the strongest oxidising power among Mn2O3, TiO and VO is B.M. (Nearest integer).
Number of colourless lanthanoid ions among the following is . Eu3+, Lu3+, Nd3+, La3+, Sm3+
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 BM (Nearest integer) (Given atomic number Sc : 21, Ti : 22, V : 23, Cr : 24, Mn : 25, Fe : 26)
The 'spin only' magnetic moment value of MO42- is BM. (Where M is a metal having least metallic radii. among Sc, Ti, V, Cr, Mn and Zn). (Given atomic number: Sc = 21, Ti = 22, V = 23, Cr = 24, Mn = 25 and Zn = 30)
The difference in the 'spin-only' magnetic moment values of KMnO4 and the manganese product formed during titration of KMnO4 against oxalic acid in acidic medium is BM. (nearest integer)
Among CrO, Cr2O3 and CrO3, the sum of spin-only magnetic moment values of basic and amphoteric oxides is 10-2 BM (nearest integer). (Given atomic number of Cr is 24 )
Among VO2+, MnO4- and Cr2O72-, the spin-only magnetic moment value of the species with least oxidising ability is BM (Nearest integer). (Given atomic number V = 23, Mn = 25, Cr = 24)
The spin-only magnetic moment value of the ion among Ti2+, V2+, Co3+ and Cr2+, that acts as strong oxidising agent in aqueous solution is BM (Near integer). (Given atomic numbers : Ti : 22, V : 23, Cr : 24, Co : 27)
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 CO2. The sum of spin-only magnetic moment values of A and B is B.M. (Nearest integer) [Given atomic number : C : 6, Na : 11, O : 8, Fe : 26, Cr : 24]
Consider the following reaction MnO2 + KOH + O2 A + H2O. Product 'A' in neutral or acidic medium disproportionate to give products 'B' and 'C' along with water. The sum of spin-only magnetic moment values of B and C is BM. (nearest integer) (Given atomic number of Mn is 25)
A first row transition metal with highest enthalpy of atomisation, upon reaction with oxygen at high temperature forms oxides of formula M2On (where n = 3, 4, 5). The 'spin-only' magnetic moment value of the amphoteric oxide from the above oxides is BM (near integer) (Given atomic number: Sc : 21, Ti : 22, V : 23, Cr : 24, Mn : 25, Fe : 26, Co : 27, Ni : 28, Cu : 29, Zn : 30)
In the reaction of potassium dichromate, potassium chloride and sulfuric acid (conc.), the oxidation state of the chromium in the product is (+) .