Tiêu đề 10. THE S-BLOCK ELEMENTS.pdf ✅

1 JEE Advanced (2024) s-Block CHEMISTRY Only One Option Correct Type Question (1-7) 1. Which of the following will liberate O2 upon hydrolysis? [Chemical reaction] (A) Pb3O4 (B) KO2 (C) Na2O2 (D) Li2O2 2. Hydrogen peroxide in its reaction with KIO4 and NH2 OH respectively, is acting as a [Chemical reaction] (A) Reducing agent, oxidising agent (B) Reducing agent, reducing agent (C) Oxidising agent, oxidising agent (d) Oxidising agent, reducing agent 3. Metal carbides on reaction with H2O form CH4. Carbide can be [Chemical reaction] (A) CaC2 (B) Mg3C2 (C) Be2C (D) SiC 4. Which is/are coloured and paramagnetic? [Properties] (A) KO2 (B) KO3 (C) Both (A) and (B) (D) None of these 5. Out of the following statements I. Cs+ is highly hydrated II. Li has highest melting point among Li, Na, K and Rb III. Only Li forms nitride out of alkali metals The correct statements are [Properties] (A) I and II only (B) II and III only (C) I and III only (D) I, II and III only 6. Select the correct statement(s) [Properties] (A) CaCO3 is more soluble in a solution of CO2 than in H2O (B) Na2CO3 is converted to Na2O ad CO2 on heating (C) Li2CO3 is thermally stable (D) Presence of CaCl2 or CaSO4 in water causes temporary hardness 7. To an acidified dichromate solution, a pinch of Na2O2 and ether is added and shaken. What is observed. [Chemical Reaction] (A) Deep violet colour (B) Red colour changing to green (C) Copious evolution of oxygen (D) Bluish-green precipitate One Or More Than One Correct Type Question (8-12) 8. Sodium sulphate is soluble in water, whereas barium sulphate is sparingly soluble because [Properties] (A) The hydration energy of sodium sulphate is more than its lattice energy. (B) The lattice energy of barium sulphate is more than its hydration energy. (C) The lattice energy has no role to play in solubility. (D) The hydration energy of sodium sulphate is less than its lattice energy. 9. The pair(s) of reagents that yield paramagnetic species is/are [Properties] (A) Na and excess of NH3 (B) K and excess of O2 (C) Cu and dilute HNO3 (D) O2 and 2-ethylanthraquinol 10. Highly pure dilute solution of sodium in liquid ammonia [Chemical Reaction] (A) Shows blue colour (B) Exhibits electrical conductivity (C) Produces sodium amide (D) Produces hydrogen gas 11. The reagent(s) used for softening the temporary hardness of water is/are [Hardness of water] (A) Ca3(PO4)2 (B) Ca(OH)2 (C) Na2CO3 (D) NaOCl Practice Sheet
2 12. MgSO4 on reaction with NH4OH and Na2HPO4 forms 2 white crystalline precipitate. What is its formula? [Chemical Reaction] (A) Mg(NH4)PO4 (B) Mg3(PO4)2 (C) MgCl2.MgSO4 (D) MgSO4 Integer Type Question (13-17) 13. Reaction of Br2 with Na2CO3 in aqueous solution gives sodium bromide and sodium bromate with evolution of CO2 gas. The number of sodium bromide molecules involved in the balanced chemical equation is______. [Chemical Reaction] 14. Total number of alkali metals (non-radioactive) which produce superoxide when burn with excess of O2 is_____. [Chemical Reaction] 15. Write atomic number difference between 1st alkali metal and alkaline earth metal of 3rd period of periodic table. [Properties] 16. Carnallite and langbeinite are the mix ore of K and Mg. KxMgCl3.6H2O is carnallite and KyMg2(SO4)3 is langbeinite respectively. Find the sum of x and y. [Properties] 17. Out of Be, Mg, Ca, Sr and Ba, number of elements which do not impart any colour to the flame, is______. [Flame Test]
3 ANSWER KEY 1. ( B ) 2. ( A ) 3 . ( C ) 4 . ( C ) 5 . ( B ) 6 . ( A ) 7 . ( A ) 8 . (A, B ) 9 . (A, B, C ) 10 . (A, B ) 11 . (B, C, D ) 1 2 . ( A ) 1 3 . ( 5 ) 1 4 . ( 3 ) 1 5 . ( 9 ) 1 6 . ( 3 ) 1 7 . ( 2 )