UPSC Chemistry 2022

1.(a) Compare average and most probable values of position of an electron in the ground state of hydrogen atom. Explain with the help of drawing, why two values differ. (10 marks)…

2.(a) An automobile tyre contains air at 320×10³ Pa at 20°C. The stem valve is removed and the air is allowed to expand adiabatically against a constant external pressure of 100×1…

(a) Identify the least stable ion of the following ions and justify your answer. OCN⁻ ONC⁻ SCN⁻ (10 marks) (b) A 74·6 g ice cube floats in the sea. The temperature and pressure of…

(a) By using the following given data, find that under what conditions is H₂ in the state corresponding to N₂ at 126 K and 1 atm ? | Gas | Tc/K | Pc/atm | |---|---|---| | H₂ | 33…

(a) The rate Law for the reaction N₂O₂(g) → 2NO(g) is of first order in the concentration of N₂O₂. Derive an expression for the time-dependent behaviour of the product concentrati…

(a) (i) Calculate the number of metal-metal bond in Cp₂Fe₂(CO)₄. (ii) Determine the structural type of the metal atom cluster, Bi₅³⁺. (10 marks) (b) Why are 4f metal ions (lanthan…

(a) Cite one example of an optically active tetracoordinated complex compound where the metal ion and donor atoms lie on a plane. Justify your answer. 10 marks (b) Consider aqueou…

(a) Which one is more stable between the two isomers? Explain. [(H₃N)₅ Cr – CN – Cr(CN)₅] [(H₃N)₅ Cr – NC – Cr(CN)₅] 10 marks (b) Draw the active site structure of Hemocyanin (Hc)…

(a) Ionization of 3,4-dichloro-1,2,3,4-tetramethylcyclobutene in SbF₅-SO₂ at –75 °C produces a reaction intermediate of its own kind. Predict the intermediate and comment on its s…

(a) Predict the products X and Y in the following reactions: (5×3=15 marks) (i) [compound] →(1) O₃ (2) H₂O₂→ X + Y (ii) [compound] →PBr₃→ [intermediate] →Br₂ (57%)→ X (iii) CH₃—CH…

The compound A, acetal of acetaldehyde, on reaction with B, under given reaction conditions, yields C and the final product D : (i) Write down the structures of the products C and…

(a) (i) Complete the following reaction by showing stepwise reaction mechanism for the formation of products : (ii) The compound A is optically active and upon treating A with alc…

(a) Write the structures of nucleosides and nucleotides, and discuss the primary structures of DNA and RNA. (10 marks) (b) Write down the products obtained after photolysis of 2-m…

(a) (i) Predict the products in the following reactions: Propose suitable mechanism to justify your answer. (ii) Giving justification, write the major and minor product(s). Commen…

(a) Discuss the different types of secondary structures of proteins and compare these structures with tertiary structure of proteins. 15 marks (b) Complete the following reactions…

(a) (i) Among the following compounds I and II, which has more carbonyl stretching frequency in IR spectra? Explain: I II 5 marks (ii) Complete the following reaction. Write the s…