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The correct statement about B₂H₆ is:

a. All B–H–B angles are of 120°. b. Its fragment, BH3, behaves as a Lewis base. c. Terminal B–H bonds have less p-character... View Article

The major product of the following chemical reaction is:

a. (CH3CH2CO)2O b. CH3CH2CHO c. CH3CH2CH3 d. CH3CH2CH2OH Answer: (b) The major product is CH3CH2CHO... View Article

Given below are two statements:

Statement-I: CeO2 can be used for oxidation of aldehydes and ketones. Statement-II: Aqueous solution of EuSO4 is a strong reducing agent. a.... View Article

Identify A in the given chemical reaction.

Answer: (d) Aromatization reaction or hydroforming reaction.... View Article

According to molecular orbital theory, the species among the following that does not exist is:

a. He2- b. He2+ c. O22- d. Be2 Answer: (d) B.O. of Be2 is zero, so it does not exist.... View Article

In Freundlich adsorption isotherm at moderate pressure, the extent of adsorption (x/m) is directly proportional to P^x. The value of x is:

a. ∞ b. 1 c. zero d. 1/n Answer: (d) x / m = px The formula is x / m = px Hence, x= 1 / n. The value of 'n' is any natural number.... View Article

Which of the following equations depicts the oxidizing nature of H₂O₂?

a. Cl2 + H2O2 → 2HCl + O2 b. KlO4 + H2O2 → KlO3 + H2O + O2 c. 2l– + H2O2 + 2H+ → I2 + 2H2O d. I2 + H2O2 + 2OH–... View Article

Ellingham diagram is a graphical representation of:

a. ΔG vs T b. (ΔG – TΔS) vs T c. ΔH vs T d. ΔG vs P Answer: (a) Ellingham diagram tells us about the... View Article

Assuming ideal behavior, the magnitude of log K for the following reaction at 25ºC is x × 10^–1. The value of x is __________. (Integer Answer)

3HC ≡ CH(g) ⇌ C6H6 (l) [Given: ΔfG° (HC = CH) = – 2.04 × 105] mol–1; ΔfG°(C6H6) = – 1.24 × 105 J mol–1; R = 8.314 J K–1 mol–1] Answer: 855... View Article

Sucrose hydrolysis in acid solution into glucose and fructose following first order rate law with a half-life of 3.33 h at 25ºC. After 9h, the fraction of sucrose remaining is f. The value of is _________× 10^–2 (Rounded off to the nearest integer)

[Assume: ln10 = 2.303, ln2 = 0.693] Answer: 81 t1/2 = 3.33h = 10 / 3h Fraction of sucrose remaining , f = ... View Article

The formula of a gaseous hydrocarbon which requires 6 times of its own volume of O₂ for complete oxidation and produces 4 times its own volume of CO₂ is C_xH_y. The value of y is

Answer: 8 CxHy + 6O2 4CO2 + y/2 H2O Applying POAC on 'O' atoms 6 × 2 = 4 × 2 + y/2 × 1 y/2 = 4 ⇒ y = 8... View Article

1.86 g of aniline completely reacts to form acetanilide. 10% of the product is lost during purification. Amount of acetanilide obtained after purification (in g) is ____× 10^–2

Answer: 243 93 g Aniline produce 135 g acetanilide 1.86 g produce 135 × 1.86 / 93 = 2.70 g At 10% loss, 90% product will be formed after... View Article

The total number of amines among the following which can be synthesized by Gabriel synthesis is _______

Answer: 3 Only 1o amines can be prepared by Gabriel synthesis.... View Article

The solubility product of PbI₂ is 8.0 × 10^–9. The solubility of lead iodide in 0.1 molar solution of lead nitrate is x × 10^–6 mol/L. The value of x is ________ (Rounded off to the nearest integer)

Given: √2 = 1.41 Answer: 141 PbI2(s) ⇌ Pb2+ (aq) + 2I- (aq) S+0.1 2s KSP (PbI2) = 8 × 109 KSP = [Pb+2][I-]2 8 × 10–9 = (S... View Article

The volume occupied by 4.75 g of acetylene gas at 50°C and 740 mmHg pressure is _______L. (Rounded off to the nearest integer) (Given R = 0.0826 L atm K^–1 mol^–1)

Answer: 5 T = 50C = 323.15 K P = 740 mm of Hg = 740 / 760 atm V = ? moles (n) = 4.75 / 26 atm V = nRT/P V = (4.75 / 26) × 0.0821 ×... View Article

C₆H₆ freezes at 5.5ºC. The temperature at which a solution of 10 g of C₄H₁₀ in 200 g of C₆H₆ freeze is ________ C. (The molal freezing point depression constant of C₆H₆ is 5.12C/m).

Answer: 1 ΔTf = i × Kf × m = 1 × 5.12 × 10 / 58200 × 1000 ∆Tf = 5.12 × 50 / 58 = 4.414 Tf(soution) =... View Article

Among the following allotropic forms of sulphur, the number of allotropic forms, which will show paramagnetism is ______.

Among the following allotropic forms of sulphur, the number of allotropic forms, which will show paramagnetism is ______. (a) α-sulphur... View Article