The relationship between rate constant and half-life period of zero order reaction is given by

• ${\mathrm{t}}_{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.}$ = [A₀] 2k

• ${\mathrm{t}}_{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.}$ = $\frac{0.693}{\mathrm{k}}$

• ${\mathrm{t}}_{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.} = \frac{\left[{\mathrm{A}}_0\right]}{2 \mathrm{k}}$

• ${\mathrm{t}}_{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.} = \frac{2 \left[{\mathrm{A}}_0\right]}{\mathrm{k}}$

van't Hoff factor of centimolal solution of K₃[Fe(CN)₆] is 3.333. Calculate the per cent dissociation of K₃[Fe(CN)₆].

• 33.33

• 0.78

• 78

• 23.33

How is ore of aluminium concentrated?

• Roasting

• Leaching

• Froth floatation

• Using Wilfley table

Which metal among the following has the highest packing efficiency?

• Iron

• Tungsten

• Aluminium

• Polonium

Half-life period of a first order reaction, A → product is 6.93 h. What is the value of rate constant?

• 1.596 h^-1

• 0.1 h^-1

• 4.802 h^-1

• 10 h^-1

Which of the following is the most stable diazonium salt?

• C₆H₅CH₂N${}_2^{+}$X^-

• CH₃N${}_2^{+}$X^-

• CH₃CH₂N${}_2^{+}$X^-

• C₆H₅N${}_2^{+}$X^-

The correct IUPAC name of [Co(NH₃)₃(NO₂)₃] is

• Triammine trinitro-N cobalt (III)

• Triammine trinitro-N cobalt (II)

• Triammine cobalt (III) nitrite

• Triammine trinitro-N cobaltate (III)

38.

The replacement of diazonium group by fluorine is known as

• Gattermann reaction

• Sandmeyer reaction

• Balz-Schiemann reaction

• Etard reaction

R-C≡N + 2H $\underset{\left(\mathrm{ii}\right) {\mathrm{H}}_3{\mathrm{O}}^{+}}{\overset{\left(\mathrm{i}\right) {\mathrm{SnCl}}_2/ \mathrm{dil}. \mathrm{HCl}}{\to }}$ RCHO + NH₄Cl, this reaction is known as

• Etard reaction

• Stephen reaction

• Hell-Volhard-Zelinsky reaction

• Balz-Schiemann reaction

Diethyl amine when treated with nitrous acid yields

• diethyl ammonium nitrite

• ethyl alcohol

• N-nitroso diethyl amine

• triethyl ammonium nitrite