List of top Questions asked in UP Board XII

Classify each of the following solids as ionic, metallic and molecular: P$_4$, Ammonium phosphate, Brass, Tetraphosphorus decoxide (P$_4$O$_{10}$), Rb, I$_2$, LiBr

Ketones do not reduce Fehling’s solution and Tollen’s reagent, while fructose containing ketonic group does. Why?

Describe Ostwald’s process for the manufacture of nitric acid. How will you detect NO$_3^-$ radical in this acid? Give equations for reactions involved.

Differentiate between molar and molal elevation constants. Give two different formulae involving these two constants for the determination of molecular mass of solute.

Differentiate between lyophilic and lyophobic colloids.

Calculate the standard e.m.f. of the following cell:
Zn $\mid$ Zn$^{2+}$ $\parallel$ Cu$^{2+}$ $\mid$ Cu
Given: $E^\circ_{(Zn^{2+}/Zn)} = -0.76 \, V$ and $E^\circ_{(Cu^{2+}/Cu)} = +0.34 \, V$

What is Kohlrausch’s law? Write its one application with example.

Amino acids are structural units of:

Give any two dehydrating properties of H$_2$SO$_4$.

1 : 1 Molar mixture of FeSO$_4$ and (NH$_4$)$_2$SO$_4$ gives test of Fe$^{2+$ ions, but 1 : 4 molar mixture of CuSO$_4$ and NH$_3$ (aq) does not give test of Cu$^{2+}$ ions. Why?}

Calculate the mass of a non-volatile solute (molar mass $40 \, \text{gm mol}^{-1}$) which should be dissolved in $114 \, \text{gm$ octane to reduce its vapour pressure to 80%.}

Formation of coloured ions is possible due to the presence of:

Unit of specific conductance is:

Molarity of pure water is:

Explain the Resonance effect in nucleophilic substitution reactions of Haloarenes.

Write chemical equations of reactions of haloalkanes with two metals.

Noble gas which forms maximum number of compounds is:

Write short notes on the following:
(i) Aldol and Crossed Aldol Condensation in Aldehyde and Ketone
(ii) Cannizzaro Reaction

Write chemical equations of five methods of preparation of Carboxylic acid.

Describe the industrial method of preparation of Ammonia giving flow diagram and chemical equation and write chemical equation of the reaction of Ammonia with (i) Copper ion, and (ii) Silver ion.

Write chemical equation for identifying primary and secondary alcohol.

Write chemical equation and mechanism of acid catalysed hydration of Alkene.

Write notes on the following:
(I) Wurtz–Fittig reaction
(II) Sandmeyer reaction

Explain Crystal Field Theory (CFT) in coordination compounds and write its limitations.

In spite of being an electron withdrawing group, why does chlorine act as ortho-para directing group in aromatic electrophilic substitution reactions?