The correct sets of quantum numbers which represents the highest energy level in an atomis:

• $\mathrm{n}=4 , \mathrm{l}=0 , \mathrm{m}=0 , \mathrm{s} = + \frac{1}{2}$

• $\mathrm{n}=3 , \mathrm{l}=0 , \mathrm{m}=0 , \mathrm{s} = + \frac{1}{2}$

• $\mathrm{n}=3 , \mathrm{l}=1 , \mathrm{m}=1 , \mathrm{s} = + \frac{1}{2}$

• $\mathrm{n}=3 , \mathrm{l}=2 , \mathrm{m}= -1 , \mathrm{s} = + \frac{1}{2}$

The vapour pressure of pure water is 25.0 mm Hg and that of an aqueous dilute solution of urea in 20mm Hg at 25°C. The molarity of the solution is:

• 12.6

• 14.9

• 13.8

• 9.6

The entropy will be positive in which of the following reaction change.

• H₂(g) + I₂ (g) $\leftrightharpoons$ 2HI (g)

• HCl(g) + NH₃ (g) $\leftrightharpoons$ N₂O(g) + 2H₂O(g)

• NH₄NO₃(s)$\leftrightharpoons$N₂O(g) + 2H₂O(g)

• MgO(s) + H₂(g) $\leftrightharpoons$ Mg(s) + H₂O(l)

Wave number of a spectral line for a given transition is xcm^-1 for He⁺ then its value for Be⁺ (iso electronic of H⁺) for same transition is:

• x cm^-1

• 4x cm^-1

• $\frac{\mathrm{x}}{4}$cm^-1

• 2x cm^-1

The hybridisation and shape of IF₅ are respectively:

• sp³d , trigonal bipyramide

• sp³d , see saw

• sp³d , square pyramidal

• sp³d , pentagonal pyramidal

On adding A to the reaction at equilibrium, AB (s) $\rightleftharpoons$ A(g) + B(g) the new equilibrium concentration of A becomes double, the equilibrium concentration of B would become:

• 1/2 of its original value

• 1/4 of its original value

• 1/8 of its original value

• Twice its original value

7.

Assuming that Hund's rule in violated,the bond order and magnetic nature of the  diatomic molecule B₂ is:

• 1 and diamagnetic

• 0 and diamagnetic

• 1 and paramagnetic

• O and paramagnetic

A solution contains 10 mL of 0.1 N NaOH and 10mL of 0.05 NH₂SO₄.pH of this solution is:

• zero

• less than 7

• greater than 7

• 7

A cylinder of compressed gas contains nitrogen and oxygen in the ratio of 3:1 by mole. The total mass of the gas mixture if the cylinder is known to contain 2.5 x 10⁴ g of oxygen will be:

• 8 x 10³ g

• 9 x 10⁴ g

• 9 x 10³ g

• 8 x 10² g

Which of the following ions has the highest value of ionic radius:

• O^2-

• F^-

• Li⁺

• B³⁺