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The purest form of commercial iron is:

a) cast iron b) wrought iron c) scrap iron and pig iron d) pig iron p>Answer: b... View Article

The number of orbitals associated with quantum number n = 5, ms = +½ is :

a) 11 b) 15 c) 25 d) 50 Answer: c n = 5; l = (n – 1) = 4; hence the possible sub-shells for n=5 are: 5s, 5p, 5d, 5f and 5g. The number of... View Article

What is the product of the following reaction?

Hex-3-ynal (i) NaBH4 (ii) PBr3 (iii) Mg/ether (iv) CO2/H3O+ Answer: b... View Article

The increasing order of pK_b for the following compounds will be :

(i) H2N-CH=NH (ii) (iii) CH3NHCH3 a) ii < iii < i b) iii < i < ii c) i < ii < iii d) ii < i < iii Answer: d... View Article

Amongst the following statements, that which was not proposed by Dalton was :

a) matter consists of indivisible atoms. b) when gases combine or reproduced in a chemical reaction they do so in a simple ratio by volume... View Article

The atomic radius of Ag is closest to :

a) Ni b) Cu c) Au d) Hg Answer: c Because of Lanthanide contraction, an increase in Zeff is observed and so, the size of Au instead of... View Article

At 35⁰C, the vapour pressure of CS₂ is 512 mm Hg and that of acetone is 344 mm Hg. A solution of CS₂ in acetone has a total vapour pressure of 600 mm Hg. The false statement amongst the following is :

a) CS2 and acetone are less attracted to each other than to themselves b) heat must be absorbed in order to produce the solution at 350C c)... View Article

The relative strength of interionic/ intermolecular forces in decreasing order is:

a) ion-dipole > dipole-dipole > ion-ion b) dipole-dipole > ion-dipole > ion-ion c) ion-ion > ion-dipole > dipole-dipole d)... View Article

In the following reaction, compound Q is obtained from compound P via an ionic intermediate.

What is the degree of unsaturation of Q? Answer: 18 The total degree of unsaturation = 18... View Article

Uranium 238 is known to undergo radioactive decay to form isotope of lead Pb 206 by emitting alpha and beta particles.

A rock initially contained 68 × 10−6 g of in three half-lives is × 1018, then what is the value of ? Answer: 1.21 Mole... View Article

Aluminum reacts with sulfuric acid to form aluminum sulfate and hydrogen. What is the volume of hydrogen gas in liters (L) produced at 300 K and 1.0 atm pressure, when 5.4 g of aluminum and 50.0 mL of 5.0 M sulfuric acid are combined for the reaction?

(Use molar mass of aluminum as 27.0 g mol−1, = 0.082 atm L mol−1 K−1) Answer: 6.15 Liter 2Al +... View Article

Consider a 70% efficient hydrogen-oxygen fuel cell working under standard conditions at 1 bar and 298 K.

Its cell reaction is H2(g) + ½ O2(g) → H2O(l) The work derived from the cell on the consumption of 1.0 × 10−3mol of... View Article

Consider the reaction A ⇌ B at 1000 K. At time ’, the temperature of the system was increased to 2000 K and the system was allowed to reach equilibrium. Throughout this experiment, the partial pressure of A was maintained at 1 bar.

Given below is the plot of the partial pressure of B with time. What is the ratio of the standard Gibbs energy of the reaction at 1000 K to that... View Article

5.00 mL of 0.10 M oxalic acid solution taken in a conical flask is titrated against NaOH from a burette using phenolphthalein indicator. The volume of NaOH required for the appearance of permanent faint pink color is tabulated below for five experiments. What is the concentration, in molarity, of the NaOH solution?

Exp. No. Vol. of NaOH (mL) 1 12.5 2 10.5 3 9.0 4 9.0 5 9.0 Answer: 0.11 H2C2O4 + 2NaOH →... View Article

The cubic unit cell structure of a compound containing cation M and anion X is shown below. When compared to the anion, the cation has a smaller ionic radius. Choose the correct statement(s).

a) The empirical formula of the compound is MX. b) The cation M and anion X have different coordination geometries. c) The ratio of M-X bond... View Article