List of top Chemistry Questions asked in UP Board XII

The solid which is electrical conductor, ductile and tensile, is called:
What do you mean by bidentate and ambidentate ligands? Give one example of each.
IUPAC name of CH\(_3\)-CH-CH\(_3\) is
The column of a solution of 0.05 mol L$^{-1}$ NaOH has diameter 2.0 cm and length 100 cm. The resistance of the column of solution is 5.55 $\times$ 10$^3$ ohm. Calculate its resistivity, conductivity and molar conductivity.

Explain the following: 
(i) NCl\(_3\) occurs but NCl\(_5\) does not. Why? 
(ii) Why are halogens strong oxidising agents? 
 

Find the osmotic pressure of $\dfrac{M}{10}$ urea solution at 27$^\circ$C. (R = 0.0821 litre atm K$^{-1}$ mol$^{-1}$)
Write short notes on the following:
(i) Aldol condensation
(ii) Decarboxylation
(iii) Cannizzaro reaction

How will you obtain Benzoic Acid from the following?
 (i) Toluene 
(ii) Benzamide 
(iii) Ethyl benzoate 
 

Write the formulae of the following coordination compounds on the basis of I.U.P.A.C. rules: 
(i) Dichloridobis(ethane-1,2-diamine)cobalt(III) chloride 
(ii) Iron(III) hexacyanidoferrate(II) 
 

At 298 K write Nernst equation for the following cell – Ni $\vert$ Ni$^{2+}$ (0.01 M) $\Vert$ Cu$^{2+}$ (0.1 M) $\vert$ Cu. If the emf of the above cell ($E_{cell}$) is 0.59 V then calculate the standard emf of the cell ($E^\circ_{cell}$)

The concentration of the solution of glucose in water is 10% (w/w). If the density of this solution is 1.20 g mL$^{-1}$, then calculate – 
(i) Molality 
(ii) Molarity 
(iii) Mole fraction of each component in solution 
 

The velocity constant for the first order reaction is $6.93 \times 10^{-3}$ min$^{-1}$. Calculate the half-life of this reaction.
Which one of the ions Fe$^{2+}$ and Fe$^{3+}$ is more paramagnetic and why?

How will you obtain the following: 
(i) Diethyl ether from Sodium ethoxide 
(ii) Benzyl alcohol from Benzyl chloride 
(iii) Propan-1-ol from Ethyl Magnesium bromide 
 

Write short notes on the following: 
(A) Wurtz–Fittig Reaction 
(B) Fittig’s Reaction 
 

Write short notes on the following: 
(i) Etard Reaction 
(ii) Gattermann–Koch Reaction 
(iii) Cannizzaro’s Reaction 
(iv) Aldol Condensation 
 

What happens, when – (Give chemical equations only) 
(i) Acetaldehyde reacts with Tollen’s reagent. 
(ii) Formaldehyde reacts with NaOH. 
(iii) Benzamide undergoes acidic hydrolysis. 
 

The initial concentration of N$_2$O$_5$ in the following first order reaction $N_2O_5(g) \longrightarrow 2NO_2(g) + \tfrac{1}{2} O_2(g)$ was $1.24 \times 10^{-2}$ mol L$^{-1}$ at 318 K. The concentration of N$_2$O$_5$ after 60 minutes was $0.20 \times 10^{-2}$ mol L$^{-1}$. Calculate the rate constant of the reaction at 318 K.
Silver crystallises in f.c.c. lattice. If edge length of the cell is $4.077 \times 10^{-8}$ cm and density is $10.5 \, \text{gm cm}^{-3}$, calculate the atomic mass of silver.
Reaction RCOOAg $\xrightarrow{Br_{2}/CCl_{4}}$ RBr is called:

Write chemical equations for the following: 
(i) Kolbe reaction 
(ii) Reimer-Tiemann reaction 
(iii) Oxidation of Phenol 
(iv) Williamson synthesis 
(v) Industrial preparation of Methanol 
 

What happens when: 

  1. Sodium Azide is heated? 
  2.  Lithium is heated with Nitrogen?
  3.  Ammonium chromate is heated? 
  4.  Nitrogen is heated with oxygen? 
  5. The aqueous solutions of Ammonium chloride and Sodium nitrite are allowed to react? 
On dissolution of 2.0 g of a non-electrolyte in 50.0 g benzene, its freezing point decreases by 0.40 K. The freezing point depression constant of benzene is 5.12 K kg mol$^{-1}$. Calculate the molar mass of the solute.
Why is chlorine atom of chlorobenzene less reactive than chlorine atom of chloroethane? Write chemical equations of reactions of chlorobenzene with (A) Cl$_2$ and (B) conc. H$_2$SO$_4$.
Write short notes on the following:
(A) Electrophilic substitution in halobenzene,
(B) Wurtz–Fittig reaction,
(C) Applications of Grignard’s reagent.