521.

The solubility of saturated solution of Ag₂CrO₄ is s mol L^-1. What is its solubility product?

• 4s³

• s³

• 2s³

• 16s²

The number of phase in a colloidal system is

• 1

• 2

• 3

• 4

Steel is heated to below red heat and then, cooled slowly. The process refers to

• hardening

• annealing

• tempering

• nitriding

Which does not give a precipitate with AgNO₃ solution?

• [Co(NH₃)₆]Cl₃

• [Co(NH₃)₅Cl]Cl₂

• [Co(NH₃)₄Cl₂]Cl

• [Co(NH₃)₃Cl₃]

At 25°C, the dissociation constant of a base, BOH, is 1.0 x 10^-12. The concentration of
hydroxyl ions in 0.01 M aqueous solution of the base would be

• 2.0 x 10^-6 mo L^-1

• 1.0 x 10^-5 mo L^-1

• 1.0 x 10^-6 mo L^-1

• 1.0 x 10^-7 mo L^-1

What is the correct relationship between the pHs of isomolar solutions of sodium oxide (pH₁), sodium sulphide (pH₂), sodium selenide (pH₃) and sodium telluride (pH₄)?

• pH₁ > pH₂ $\approx$pH₃ > pH₄

• pH₁ < pH₂ $<$pH₃ < pH₄

• pH₁ < pH₂ $<$pH₃ $\approx$ pH₄

• pH₁ > pH₂ $>$pH₃ > pH₄

A solution of urea (mol. mass 56g mol^-1) boils at 100.18°C at the atmospheric pressure. If k_f and k_b for water are 1.86 and 0.512 K kg mol^-1 respectively, the above solution will freeze at

• -6.54°C

• 6.54°C

• 0.654°C

• - 0.654°C

If the solubility of an aqueous solution of Mg(OH)₂ , be X mole litre then k_sp of Mg(OH)₂ is:

• 4X³

• 108X⁵

• 27X⁴

• 9X

A storage battery contains a solution of H₂SO₄ 38% by weight. At this concentration, the van't Hoff factor is 2.50. At what temperature will the battery contents freeze? (K_f =1.80 mol' kg)

• 243.92 K

• 298 K

• 240.92 K

• 273 K

The freezing point depression of 0.001 m K_x[Fe(CN)₆] is 7.1x 10^-3 K. The value of x will be [Given, K_f = 1.86 KKg mol^-1 for water].

• 2

• 4

• 3

• 1