Threshold frequency of a metal is 5 $\text{×}$ 10¹³ s^-1 upon which 1 x 10¹⁴s^-1 frequency light is focused. Then the maximum kinetic energy of emitted electron is

• 3.3 $\text{×}$ 10^-21

• 3.3 $\text{×}$ 10^-20

• 6.6 $\text{×}$ 10-²³

• 6.6 $\text{×}$ 10^-20

At equilibrium which is correct?

• $\text{∆}$G = 0

• $\text{∆}$S = 0

• $\text{∆}$H = 0

•  $\text{∆}$${\text{G}}^{°}$= 0

Arrange the following gases in order of their critical temperature.
NH₃, H₂O, CO₂, O₂

• NH₃ > H₂O > CO₂ > O₂

• O₂ > CO₂ > H₂O > NH₃

• H₂O > NH₃ > CO₂ > O₂

• CO₂ >O₂ >H₂O > NH₃

Bond dissociation energy of CH₄ is 360 kJ/mol and C₂H₆ is 620 kJ/mol. Then bond dissociation energy of C-C bond is

• 170 kJ/mol

• 50 kJ/mol

• 80 kJ/mol

• 220 kJ/mol

In Bohr's Orbit, $\frac{\mathrm{nh}}{2\mathrm{\pi }}$ indicates

• Momentum

• Kinetic energy

• Potential energy

• Angular momentum

6.

Which has the highest pH?

• CH₃COOK

• Na₂CO₃

• NH₄Cl

• NaNO₃

$\frac{{\mathrm{K}}_{\mathrm{p}}}{{\mathrm{K}}_{\mathrm{c}}}$ for following reaction will be ${\mathrm{CO}}_{\left(\mathrm{g}\right)}+\frac{1}{2} {\mathrm{O}}_{2\left(\mathrm{g}\right)}\to {\mathrm{CO}}_{2\left(\mathrm{g}\right)}$.

• RT

• $\frac{1}{\mathrm{RT}}$

• $\frac{1}{\sqrt{\mathrm{RT}}}$

• $\frac{\mathrm{RT}}{2}$

The dipole moment is minimum in

• NH₃

• NF₃

• SO₂

• BF₃

At 60° and 1 atm, N₂O₄ is 50% dissociated into NO₂ then K_P is

• 1.33 atm

• 2 atm

• 2.67 atm

• 3 atm

pK_a increases in benzoic acid when substituent "x" is bonded at para-position, then "x" is

• -COOH

• -NO₂

• -CN

• -OCH₃