List of top Questions asked in UP Board XII- 2026

(i) Write the IUPAC name of the following coordination compounds: (a) K3[Cr(C2O4)3] (b) [Co(NH3)5(CO3)]Cl. (ii) Write the electronic configuration of the following: (a) Cr3+ (b) Cu.
Explain the structure of Nucleic Acid.
Explain the ring structure of glucose. What happens when D-glucose reacts with the following reagents? (i) Bromine water (ii) Hydroxylamine.
Write chemical equations of three methods of preparation and two chemical properties of benzaldehyde.
OR
Write short notes on the following: (i) Aldol condensation (ii) Cross aldol condensation (iii) Cannizzaro reaction (iv) Hell-Volhard-Zelinsky reaction (v) Kolbe electrolysis.
Explain with reasons:
(i) Transition metals show variable valency (variable oxidation states).
(ii) Copper is considered a transition metal even though it has a completely filled d-orbital \((3d^{10})\) in its \(+1\) state.
Explain the type of isomerism shown by the following complexes and give the structure of the isomers:
(i) \([\text{Co(NH}_3)_5(\text{NO}_2)](\text{NO}_3)_2\)
(ii) \([\text{Cr(NH}_3)_6][\text{Co(CN)}_6]\)
(iii) \([\text{Fe(NH}_3)_2(\text{CN})_4]^-\)
Explain electrode potential and standard electrode potential. The following reaction takes place in a cell: \[ \text{Zn(s)} + \text{Co}^{2+} \rightleftharpoons \text{Co(s)} + \text{Zn}^{2+} \] Calculate the standard cell potential \(E^\circ_{cell}\) of the cell. Given: \(E^\circ_{(\text{Zn} \rightarrow \text{Zn}^{2+})} = 0.76\,\text{V}\) and \(E^\circ_{(\text{Co} \rightarrow \text{Co}^{2+})} = 0.28\,\text{V}\) (oxidation potentials).
Discuss the factors that affect the velocity (rate) of a chemical reaction.
0.32 g of a new compound was dissolved in 25 g of water. The freezing point of this solution was found to be \(-0.201\,^\circ\text{C}\). Determine the molecular weight of this new compound. For water \(K_f = 1.86\,^\circ\text{C}\;\text{kg mol}^{-1}\).
What is Lanthanide contraction? What are the consequences of Lanthanide contraction?
Draw a diagram to show the splitting of d-orbitals in an octahedral crystal field.
The velocity constant \(K\) for a first order reaction was found to be \(5.5 \times 10^{-14}\,s^{-1}\). Calculate the half life of this reaction.
How will you obtain the following from phenol? (i) Picric acid (ii) Benzoquinone.
Is the following reaction possible or not? Explain with reasons. \[Zn(NO_3)_2 + 2Ag \rightarrow 2AgNO_3 + Zn\]
Write chemical equations of the Etard reaction and the Gattermann-Koch reaction.
In which cell does the following reaction take place? \[2H_2(g) + O_2(g) \rightarrow 2H_2O(l)\]
The velocity (rate) constant of a second order reaction is generally expressed as:
The distinction between aldehydes and ketones can be made using:
Which of the following solutions will have a maximum boiling point?
The order of reaction for which the unit of the velocity (rate) constant is \(mol\,L^{-1}\,s^{-1}\) is:
(i) Explain Hinsberg test for the distinction between primary, secondary and tertiary amines. (ii) Write a short note on Carbylamine reaction. (2½+2½=5)
OR
What happens when (write chemical equations only): (i) Aqueous solution of benzene diazonium chloride is heated (ii) Acetamide is reacted with aqueous KOH in the presence of bromine (iii) Aniline reacts with sodium nitrite and dil. HCl at 0°C (iv) Aniline reacts with acetic anhydride in the presence of pyridine (v) Aniline reacts with Bromine water. (1+1+1+1+1=5)
Write short notes on the following. (i) Cross aldol condensation (ii) Stephen reaction (iii) Etard reaction. (2+1½+1½=5)
OR
How will you obtain (write chemical equations only): (i) Ethanoic anhydride from Ethanoic acid (ii) Benzoic acid from Ethyl benzoate (iii) Benzamide from benzoic acid. (2+1½+1½=5)
Write short notes on the following: (i) Freons (ii) Sandmeyer reaction (iii) Friedel Craft acylation of haloarene. (2+1½+1½=5)
OR
What happens when (write chemical equation only): (i) Propene reacts with HI (ii) Ethyl bromide reacts with magnesium in the presence of dry ether (iii) Chlorobenzene is heated with sodium in dry ether (iv) The mixture of chlorobenzene and methyl chloride is heated with sodium in the presence of dry ether (v) Isopropyl alcohol reacts with conc. HCl and ZnCl2. (1+1+1+1+1=5)
(i) Write notes on Williamson's synthesis. (ii) Write the chemical equation for the preparation of phenol from cumene. (iii) How will you convert phenol to salicylaldehyde? (2+1½+1½=5)
OR
What happens when (write chemical equations only): (i) Phenol reacts with dil. HNO3 (ii) Ethyl methyl ether is heated with conc. HI (iii) Phenol is heated with conc. HNO3 in the presence of conc. H2SO4 (iv) Ethyl alcohol reacts with thionyl chloride in the presence of pyridine (v) Phenol reacts with bromine water. (1+1+1+1+1=5)
What is the order of reaction? Derive the integrated rate equation for a first order reaction and obtain an expression for the half life period of this reaction. (1+2+1=4)