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The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is 1.0×10^–3 s^–1and the activation energy E_a = 11.488 kJ mol^–1, the rate constant at 200 K is __________×10^–5s^–1.(Round off to the Nearest Integer).

Answer: 10 ⇒ ⇒ K1 = 10–4 So, x × 10–5 = 10–4 ⇒ x = 10 (Given: R = 8.314 J Mol–1... View Article

Two salts A₂X and MX have the same value of solubility product of 4.0×10^–12. The ratio of their molar solubilities i.e. [latex]frac{S(A_{2}X)}{S(MX)}[/latex] = _____________. (Round off to the Nearest Integer).

Answer: 50 A2X(s) ⇌ 2A+(aq) + X2–(aq) Solubility: (x) mole / L (2x) (x) ⇒ Ksp = 4 × 10–12 = [A+]2 [X–] = 4x3 ⇒... View Article

A 6.50 molal solution of KOH (aq.) has a density of 1.89 g cm^–3The molarity of the solution is __________ mould m^–3 (Round off to the Nearest Integer).

[Atomic masses : K : 39.0 u; O: 16.0 u; H: 1.0 u] Answer: 9 12285 – 364M = 1000M 1364 M = 12285 M = 9... View Article

For the reaction A(g) ⇌ B(g) at 495 K, Δ_rG^o = –9.478 kJ mol^–(1)

If we start the reaction in a closed container at 495 K with 22 millimoles of A, the amount of B in the equilibrium mixture is... View Article

The equivalents of ethylene diamine required to replace the neutral ligands from the coordination sphere of the trans-complex of CoCl₃.4NH₃ is __________. (Round off to the nearest Integer).

Answer: 2 COCl3 .4NH3 or [CO(NH3)4Cl2]Cl... View Article

A certain element crystallizes in a bcc lattice of unit cell edge length 27Å. If the same element under the same conditions crystallises in the fcc lattice, the edge length of the unit cell in Å will be _________. (Round off to the Nearest Integer).

[Assume each lattice point has a single atom] [Assume √3 = 1.73, √2 = 1.41] Answer: 33 For BCC unit cell, √3a = 4R a =... View Article

AB₂ is 10% dissociated in water to A²⁺ and B^–. The boiling point of a 10.0 molal aqueous solution of AB₂ is ____________ ^oC. (Round off to the Nearest Integer)

[Given: Molal elevation constant of water Kb = 0.5 K kg mol–1 boiling point of pure water = 100oC] Answer: 106 ΔTb = iKbm α =... View Article

Complete combustion of 750 g of an organic compound provides 420 g of CO₂ and 210 g of H₂O. The percentage composition of carbon and hydrogen in organic compounds is 15.3 and _______ respectively. (Round off to the Nearest Integer).

Answer: 3 Liebig method: % of H-element = =... View Article

If the equation below is balanced with integer coefficients, the value of c is__________. (Round off to the nearest integer)

If the equation below is balanced with integer coefficients, the value of c is__________. (Round off to the nearest integer) 2MnO-4 + bC2O2-4 +... View Article

The functions of antihistamine are:

a. Antiallergic and Analgesic b. Antacid and antiallergic c. Antiallergic and antidepressant d. Analgesic and antacid Answer: (b) Based on NCERT... View Article

The process that involves the removal of sulphur from the ores is:

a. Refining b. Roasting c. Smelting d. Leaching Answer: (b) Roasting removes S as SO2 S + O2 → SO2... View Article

Match List – I with List – II:Name of oxo acid, Oxidation state of ‘P’

Match List – I with List – II: List-I Name of oxo acid List-II Oxidation state of 'P' (a)... View Article

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R Assertion A: The H–O–H bond angle in a water molecule is 104.5^o Reason R: The lone pair – lone pair repulsion of electrons is higher than the bond pair-bond pair repulsion.

In the light of the above statements, choose the correct Ans: from the options given below: a. A is false but R is true b. A is true but R is... View Article

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Enol form acetone [CH3COCH3]... View Article

Given below are two statements: Statement I: Both CaCl₂.6H₂O and MgCl₂.8H₂O undergo dehydration on heating. Statement II: BeO is amphoteric whereas the oxides of other elements in the same group are acidic.

a. Statement I is true but statement II is false b. Both Statement I and Statement II are false c. Statement I is false but statement II is... View Article

Given below are two statements: Statement I: The E^o value for Ce⁴⁺/Ce³⁺ is +1.74 V. Statement II: Ce is more stable in Ce⁴⁺ state than Ce³⁺ state.

a. Both Statement I and Statement II are correct b. Statement I is incorrect but statement II is correct c. Both Statement I and Statement II... View Article