11.

The pOH of a solution is 6.0. Its pH will be

• 6

• 8

• 0

• 14

Solubility products of Al(OH)₃ and Zn(OH)₂ are 8.5 × 10^-23 and 1.8 × 10^-4 respectively. If both Al³⁺ and Zn²⁺ ions are present in a solution, which one will be precipitated first on addition of NH₄OH?

• Al(OH)₃

• Zn(OH)₂

• Both (a) and (b)

• None of these

In a reversible isothermal process, the change in internal energy is

• zero 

• positive

• negative

• None of these

Based on the following thermochemical equations

H₂O (g) + C(s) → CO (g) + H₂ (g); $∆$H = 131 kJ

CO (g) + $\frac{1}{2}$ O₂(g) → CO₂ (g); $∆$H = -282 kJ

H₂ (g) + $\frac{1}{2}$O₂ (g) → H₂O (g); $∆$H =-242 kJ

C (s) + O₂ (g) → CO₂ (g); $∆$H = X kJ

the value of X will be

• -393 kJ

• -655 kJ

• +393 kJ

• +655 kJ

The sky looks blue due to

• dispersion effect

• reflection

• transmission

• scattering

The first ionisation potential of Na, Mg, Al and Si are in the order

• Na < Mg > Al < Si

• Na > Mg > Al > Si

• Na < Mg < Al > Si

• Na > Mg > Al < Si

Elements of which group form anions most readily?

• Oxygen group

• Nitrogen group

• Halogens

• Alkali metals

Which of the following is paramagnetic?

• [Ni(CO)₄]²⁺

• [Co(NH₃)₆]²⁺

• [Ni(CN)₄]^2-

• [NiCl₄]^2-

Which of the following elements is present in red blood cells of man?

• Fe

• Ra

• Co

• None of these

The weakest acid among the following is

• CH₃COOH

• CH₂ClCOOH

• CHCl₂COOH

• CCl₃COOH