Sodium thiosulphate is used in photography

• as AgBr grain is reduced to non-metallic silve

• to convert metallic silver into silver salt

• to remove reduced silver

• to remove undecomposed AgBr in the form of Na₃[Ag(S₂O₃)₂] (a complex salt)

Ice crystallises in a hexagonal lattice. At the low temperature, the lattice constants were a = 4.53 Å and b = 7.41 Å. How many H₂O molecules are contained in a unit cell? [d(ice) =0.92 g /cm³ ]

• 4

• 3

• 2

• 1

A 0.001 molal solution of [Pt(NH₃)₄Cl₄] in water had a freezing point depression of 0.0054°C. If K_f for water is 1.80, the correct formulation of the above molecules is

• [Pt(NH₃)₄Cl₃]Cl

• [Pt(NH₃)₄Cl₂]Cl₂

• [Pt(NH₃)₄Cl]Cl₂

• [Pt(NH₃)₄Cl₄]

If M is molecular weight of solvent, K_b is molal elevation constant, T_b is its boling point p° is its vapour pressure at temperature T and p_s is vapour pressure of its solution having a non- volatile solute at T K , then

• $\frac{{\mathrm{p}}^{°}-{\mathrm{p}}_{\mathrm{s}}}{{\mathrm{p}}^{°}}= \frac{∆{\mathrm{T}}_{\mathrm{b}}}{{\mathrm{K}}_{\mathrm{b}}}\times \mathrm{M}$

• $\frac{{\mathrm{p}}^{°}-{\mathrm{p}}_{\mathrm{s}}}{{\mathrm{p}}^{°}}=\frac{{\mathrm{K}}_{\mathrm{b}}}{∆{\mathrm{T}}_{\mathrm{b}}}\times \mathrm{M}$

• $\frac{{\mathrm{p}}^{°}-{\mathrm{p}}_{\mathrm{s}}}{{\mathrm{p}}^{°}}=\frac{{\mathrm{K}}_{\mathrm{b}}}{∆{\mathrm{T}}_{\mathrm{b}}}\times \frac{\mathrm{M}}{1000}$

• $\frac{{\mathrm{p}}^{°}-{\mathrm{p}}_{\mathrm{s}}}{{\mathrm{p}}^{°}}=\frac{∆{\mathrm{T}}_{\mathrm{b}}}{{\mathrm{K}}_{\mathrm{b}}}\times \frac{\mathrm{M}}{1000}$

Which of the following statements is correct for Tyndall effect?

• Scattering and polarising of light by small suspended particles is called Tyndall effect

• Tyndall effect of colloidial particles is due to dispersion of light

• Tyndall effect is due to refraction of light

• Tyndall effect is zig-zag motion of suspended particles.

Calculate the ionic radius of a Cs⁺ ion, assuming that the cell edge lenght for CsCl is 0.4123 nm and that the ionic radius of a Cl^- ion is 0.181 nm

• 0.176 nm

• 0.231 nm

• 0.357 nm

• 0.166 nm

The pair of molecules forming strongest hydrogen bonds are

• HCOOH and CH₃COOH

• CH₃COOH and CHCl₃

• H₂O and H₂

• SiF₆ and SiH₄

Which of the following reasonating structures is not correct for

Which of the following represents the correct order of the acidity in the given compound?

• ClCH₂COOH < BrCH₂COOH< CH₃COOH < FCH₂COOH

• CH₃COOH < BrCH₂COOH < ClCH₂COOH < FCH₂COOH

• FCH₂COOH < ClCH₂COOH < BrCH₂COOH < CH₃COOH

• CH₃COOH < ClCH₂COOH < BrCH₂COOH < CH₃COOH

40.

What will be the major product when 2-amino propane is treated with nitrous acid?

• Propane-2-ol

• Cyclopropene

• Propanol

• 2-rntropropane