List of top Chemistry Questions

Discuss the chelate effect with an example. Explain the nature of bonding in \( [\text{Fe}(\text{CN})_6]^{4-} \) on the basis of valence bond theory. (2+2=4)
(i) Write a short note on the cyclic structure of glucose.
(ii) What is the difference between a nucleoside and a nucleotide? (2+2=4)
What is the order of reaction? Derive the integrated rate equation for a first order reaction and obtain an expression for the half life period of this reaction. (1+2+1=4)
An aqueous solution of glucose is 10% (w/w). What would be the molality and mole fraction of each component in the solution? (Molar mass of glucose = 180 g mol⁻¹)
Define molar conductivity of a solution of an electrolyte and explain Kohlrausch law.
Describe the effect of concentration and temperature on the rate of chemical reaction. Rate constant K = 5.5 × 10⁻¹⁴ s⁻¹ for a first order reaction. Calculate the half life time of this reaction.
(i) Explain with reason that transition metals generally form coloured compounds.
(ii) Write a short note on the lanthanoid contraction.
How will you differentiate the following?
(i) Acetaldehyde and acetone
(ii) Acetaldehyde and formaldehyde
Differentiate between fibrous and globular proteins.
Define molal elevation constant. (2)
Explain reverse osmosis and write any one example of artificial semipermeable membrane. (1+1=2)
Alkyl chloride reacts with aqueous KOH to form alcohol while in the presence of alcoholic KOH, alkene is obtained as major product. Explain. (2)
Mention the different steps for the preparation of potassium permanganate from pyrolusite ore and draw the structure of permanganate ion. (1+1=2)
Ortho nitrophenol is more acidic than phenol. Explain. Draw the resonance structures of their corresponding phenoxide ion. (2)
Write the IUPAC names of the following coordination compounds.
(i) \( [Cr(NH_3)_2Cl_2(en)]Cl \)
(ii) \( [Pt(NH_3)_4Cl_2][PtCl_4] \) (1+1=2)
Which of the following is the most basic compound?
Which of the following ions has highest magnetic moment?
Which of the following complexes exhibit linkage isomerism?
Benzyl alcohol is obtained from benzaldehyde by the following reaction.
The chemical name of vitamin \( B_1 \) is
Read the following assertion and reason and choose the correct alternative.
Assertion: Elevation in boiling point for two isotonic solutions is same.
Reason: Boiling point depends upon the concentration of the solute.
(b) (i) Describe any one method for the identification of primary, secondary and tertiary amines. Also write the chemical reactions. (ii) Write a short note on Gabriel Phthalimide Synthesis. (3+2=5)
OR
How will you obtain (write chemical equations only): (i) Benzene diazonium chloride from Aniline (ii) Methylamine from Acetamide (iii) Aniline from Nitrobenzene. (2+1½+1½=5)
(a) Write short notes on the following: (i) Cannizzaro's reaction (ii) Aldol condensation (iii) Gattermann-Koch reaction. (2+1½+1½=5)
OR
How will you obtain (write chemical equations only): (i) Benzaldehyde from Toluene (ii) Benzamide from Benzoic acid (iii) Phthalimide from Phthalic acid (iv) m-nitrobenzaldehyde from Benzaldehyde (v) Benzaldehyde from Benzene. (1+1+1+1+1=5)
(i) Explain the mechanism of the formation of ethanol by acid catalyzed hydration of ethene. (ii) Explain hydroboration-oxidation reaction with an example. (2½+2½=5)
OR
What happens when? (Write chemical equations only) (i) Ethyl bromide reacts with sodium ethoxide. (ii) Phenol is heated with conc. HNO3 in the presence of conc. H2SO4. (iii) Methoxybenzene is heated with acetyl chloride in the presence of anhydrous AlCl3. (iv) Phenol reacts with chloroform in the presence of aqueous NaOH. (v) Ethyl methyl ether is heated with conc. HI. (1+1+1+1+1=5)
A first order reaction takes 10 min for 20% decomposition. Calculate the time taken for the reaction to go to 80% decomposition. (Given, \( \log_{10}2 = 0.3010 \))