List of top Chemistry Questions

State whether entropy change is positive or negative in the following examples : (i) Melting of ice (ii) Vaporisation of a liquid Explain ‘common ion effect’ with example.
Draw a neat and labelled diagram of a lead accumulator cell. Write the overall reactions taking place at cathode and anode during discharging of the cell.
Define a unit cell. Which colour is shown by NaCl crystal due to formation of F-centre? Why does fluorine show anomalous behaviour in ‘17 group’ elements?
\( \Delta \)H for formation of ethane gas is \( -84.4 \) kJ at 300 K. Calculate \( \Delta \)U for the reaction.
Write the reducing agents used to convert Fe\(_2\)O\(_3\) to ‘Fe’ in the reduction zone of blast furnace. Write chemical equations involved in : (i) Carbylamine reaction for ethylamine. (ii) Hoffmann Bromamide degradation for acetamide.
Define zero order reaction. A reaction takes place in two steps : (i) NO(g) + Cl\(_2\)(g) \( \rightarrow \) NOCl\(_2\)(g) (ii) NOCl\(_2\)(g) + NO(g) \( \rightarrow \) 2NOCl(g). Write the overall reaction and identify the reaction intermediate.
Explain Cannizzaro’s reaction with the help of benzaldehyde. Write the reaction for the conversion of cyclohexene to adipic acid.
An element with molar mass 27 g/mol forms a cubic unit cell with edge length 405 pm. If density of the crystal is g cm\(^{-3}\), identify the type of unit cell. Derive the equation of Raoult’s law for binary solution containing non-volatile solute.
Write the formula to calculate EAN. Explain formation of [CO(NH\(_3\))\(_6\)]\(^{3+}\) complex ion with respect to : (i) Type of hybridisation (ii) Magnetic property
Mention the types of polymers formed on the basis of intermolecular forces. Write any two uses of low density polyethylene.
Calculate spin only magnetic moment of M\(^{2+}\) ion. [atomic number of M = 26] Write condensed electronic configuration of Gadolinium [Z = 64].
What is atom economy? Explain any two applications of nanomaterials.
Define conjugate acid-base pair. The hydroxyl ion concentration in aqueous solution of NaOH is 2 \( \times \) 10\(^{-4}\) mol dm\(^{-3}\). Calculate pH of the solution.
Identify ‘A’ and ‘B’ in the following reaction and rewrite the complete reaction : \[ \text{CH}_3\text{-CH=CH}_2 \xrightarrow[\text{Peroxide}]{\text{HBr}} \text{A} \xrightarrow[\text{-KBr}]{\text{alcoholic KCN}} \text{B} \]
Write the reactions for the action of following reagents on phenol : (i) Nitrating mixture (ii) Zinc dust What is the action of phosphorous pentachloride on ethyl methyl ether?
Write the structural formula and IUPAC name of the alcohol having molecular formula C\(_4\)H\(_{10}\)O which does not undergo oxidation under normal condition.
Write the reaction for the preparation of : (i) acetaldehyde by Rosenmund reaction. (ii) benzaldehyde by Gatterman-Koch formylation.
Write the general electronic configuration of 3d series. Draw the structures of sulphuric acid and thiosulphuric acid.
Write anomalous behaviour of oxygen with respect to : (i) Atomicity (ii) Oxidation state (iii) Magnetic property (iv) Nature of hydrides.
Write the differences between lanthanoids and actinoids.
Write preparation of glucose from sucrose.
What is the action of : (i) Liquid bromine in acetic acid on anisole. (ii) Soda-lime on sodium acetate?
Define: Osmotic pressure
State Henry's law.
Explain ionization isomers with suitable example in complexes.