List of top Chemistry Questions asked in UP Board XII

Why metals show their maximum oxidation states in oxides and fluorides?
Explain with reason:
(i) Cr^{2+} is a reducing agent while Mn^{3+} is an oxidising agent, while both have \(d^4\) configuration.}
Transition metals generally form coloured compounds.
Explain Raoult's Law. The vapour pressure of chloroform (\( \text{CHCl}_3 \)) and dichloromethane (\( \text{CH}_2\text{Cl}_2 \)) are 200 mm Hg and 4.5 mm Hg respectively at 298 K. Calculate the vapour pressure of the solution formed by mixing 51 g of \( \text{CHCl}_3 \) and 20 g of \( \text{CH}_2\text{Cl}_2 \) at 298 K.
Give the name of two water-soluble vitamins and diseases due to deficiency of them.
The resistance of a column formed by a 0.10 mol L^{-1} concentrated solution is 6.5 × 10^3 ohm. Its diameter is 1 cm and length is 50 cm. Calculate its resistivity, conductivity and molar conductivity.
Differentiate between the following:
(i) Propanal and Propanone,
(ii) Phenol and Benzoic acid.
Explain the following reactions with suitable chemical equations:
(i) Wurtz reaction
(ii) Wurtz-Fittig reaction
Alcohols are more soluble in water in comparison to hydrocarbons of comparable molecular weight. Explain.
Why is there always a decreasing tendency of solubility of gases in liquid on rising temperature?
How many oxidation states are exhibited by lanthanides?
Show the geometrical isomers of \([Fe(NH_3)_2(CN)_4]\).
The correct IUPAC name for \( CH_2 = CHCH_2NHCH_3 \) is:
Calculate molality of a solution of 5.0 g of ethanoic acid (CH}_3\textbf{COOH) in 150.0 g of benzene.
Sweetest sugar is:
Reagent, which do not react with acetone and benzaldehyde:
How many ions will be generated from the solution of the complex \( [Co(NH_3)_6]Cl_2 \)?
Magnetic moment of a bivalent ion in aqueous solution will be, if its atomic number is 25:
Give an example of such solid solution in which solute is gas.
Write short notes on the following: Coupling reaction:
How may the following be obtained?
Write the chemical equation for the preparation of Aniline and write the chemical equation of its reaction with the following:
Write the chemical equation for the preparation of acetaldehyde and write a note on Aldol condensation and cross-Aldol condensation.
Explain the mechanism of the reaction of diethyl ether with HI.
Explain the mechanism of dehydration of alcohol.