The weight of one molecule of a compound C₆₀H₁₂₀ is :

• 1.2 x 10^-20 g

• 5.025 x 10²³ g

• 1.4 x 10^-21 g

• 6.023 x 10²³ g

If P is pressure and $\mathrm{\rho }$ is density of a gas, then P and $\mathrm{\rho }$ are related as :

• P $\propto$ $\mathrm{\rho }$

• P $\propto \left(\frac{1}{\mathrm{\rho }}\right)$

• P $\propto {\mathrm{\rho }}^2$

• P $\propto \left(\frac{1}{{\mathrm{\rho }}^2}\right)$

Quantum numbers of an atom can be defined on the basis of :

• Hund's rule

• Pauli's exclusion principle

• Aufbau's principle

• Heisenberg's uncertainty principle

Which of the following has maximum energy ?

• 
  3s                      3p                                     3d

  $⥮$

  $⥮$

  $\uparrow$

  $\uparrow$

• 3s                      3p                                   3d

  $⥮$

  $\uparrow$

  $\uparrow$

  $\uparrow$

  $\uparrow$

• 3s                     3p                                     3d

  $⥮$

  $\uparrow$

  $\uparrow$

  $\uparrow$

  $\uparrow$

  $\uparrow$

• 3s                    3p                                 3d

  $⥮$

  $\uparrow$

  $\uparrow$

  $\uparrow$

  $\uparrow$

5.

At 80°C, distilled water has H⁺ ions concentration equal to 1 x 10^-6 mole/litre. The value of K_W at this temperature will be :

• 1 X 10^-6

• 1 X 10^-12

• 1 X 10^-9

• 1 X 10^-15

The pH of solution containing 0.10 M sodium acetate and 0.03 M acetic acid is :

(pK_a for CH₃COOH = 4.57)

• 4.09

• 6.09

• 5.09

• 7.09

Spectrum of Li²⁺ is similar to that of :

• H

• Be

• He

• Ne

Which of the following molecule has highest bond energy ?

• F-F

• N-N

• C-C

• O-O

The heat of neutralization of a strong base and a strong acid is 57 kJ. The heat released when 0.5 mole of HNO₃ solution is added to 0.20 moles of NaOH solution, is :

• 11.4 kJ

• 34.7 kJ

• 23.5 kJ

• 58.8 kJ

The solubility of CuBr is 2 x 10^-4 mol/L at 25°C. The K_SP value for CuBr is :

• 4 x 10^-8 mol² L^-2

• 4 x 10^-4 mol² L^-2

• 4 x 10^-11 mol² L^-2

• 4 x 10^-15 mol² L^-2