List of top Chemistry Questions asked in UP Board XII

Write structures of the following compounds: (i) 2-Chloro-3-methylpentane
(ii) 1,4-dibromobut-2-ene
(iii) 1-Bromo-2,2-dimethylpropane
(iv) 1-Bromo-2-methylbut-2-ene
(v) 1-Chloro-2-methylbenzene
Write formula of the following coordination compounds:
(x) Tetraammine diaqua cobalt (III) chloride
(y) Potassium trioxalato chromate (III)
The colour of dilute solutions of [Fe(CN)$_6$]$^{4-$ and [Fe(H$_2$O)$_6$]$^{2+}$ are different. Explain.}
A first order reaction completes 20% in 10 minutes. Calculate the time taken for 75% completion.
Explain the following reactions with examples: (i) Kolbe reaction
(ii) Reimer–Tiemann reaction
(iii) Williamson Ether synthesis
Write the products of the following reactions:
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Explain the following terms: (i) Zwitter ion
(ii) Peptide bond
(iii) Primary structure of protein
(iv) Polysaccharides
What do you understand by dehydration reaction? Write the mechanism of dehydration reaction of alcohol.
What is elevation of boiling point? A liquid has boiling point 353.23 K. The boiling point of solution becomes 354.11 K after dissolving 1.8 g non-volatile solute of molar mass 58 g mol$^{-1$ to 90 g liquid. Calculate boiling point elevation constant for the liquid.}
How do the following factors affect the velocity of reaction? (i) Concentration
(ii) Temperature
(iii) Catalyst
Explain in brief the Faraday's laws of Electrolysis. CuSO$_4$ solution was electrolysed for 20 minutes with 2.0 ampere current. What will be the mass of precipitated copper at cathode?
Describe the method of preparation of potassium permanganate. How does acidic potassium permanganate react with the following? Give ionic equations: (i) H$_2$S (ii) Fe (iii) iodide ion.
Boiling point of propanol is greater than butane. Explain.
The spin-only magnetic moment value of \([\mathrm{MnBr}_4]^{2-}\) is \(5.9\,\mathrm{BM}\). What will be the geometry of the complex ion?
Explain Cannizzaro reaction with chemical equation.
A cell in which the following reaction occurs:
\[ \text{Zn}_{(s)} + \text{Cu}^{2+}_{(aq)} \rightarrow \text{Zn}^{2+}_{(aq)} + \text{Cu}_{(s)} \] has standard electrode potential \(E^\circ_{\text{cell}} = 1.1~\text{V}\) at \(298~\text{K}\). Calculate the standard Gibbs energy and the equilibrium constant of the cell reaction.
What is nucleic acid? Write two important properties of them.
Transition metals and their maximum compounds are paramagnetic. Explain it.
Write the uses of carbon tetrachloride and chloroform.
Best method of preparing primary amines from alkyl halides without changing the number of carbon atoms in the chain is
Explain Raoult's Law.
In a solution 30 mass percent of benzene is dissolved in carbon tetrachloride. Calculate mole fraction of benzene.
The correct order of increasing acid strength is
Oxidation number of cobalt in K[Co(CO)$_4$] is
Which of the following gives a positive Fehling's solution test?