List of top Chemistry Questions

The position of both, an electron and a helium atom is known within 1.0 nm. Further the momentum of the electron is known within \( 5.0 \times 10^{-26} \, \text{kg} \, \text{ms}^{-1} \). The minimum uncertainty in the measurement of the momentum of the helium atom is:

In a set of reactions, ethylbenzene yields a product D. \[ \text{CH}_3\text{C}_6\text{H}_5 \xrightarrow{K\text{MnO}_4} \text{Br}_2 \xrightarrow{\text{FeCl}_3} \text{C}_6\text{H}_5\text{COOH} \xrightarrow{\text{H}_2\text{O}} \text{D} \] Identify D:

In fructose, the possible optical isomers are:

A galvanic cell is set up from electrodes A and B Electrode A: \( \text{Cr}_2\text{O}_7^{2-} / \text{Cr}^{3+}, \, E^\circ_{\text{red}} = +1.33 \, \text{V} \) Electrode B: \( \text{Fe}^{3+} / \text{Fe}^{2+}, \, E^\circ_{\text{red}} = +0.77 \, \text{V} \) Which of the following statements is false?

In a set of reactions, acetic acid yields a product D: \[ \text{CH}_3\text{COOH} \xrightarrow{\text{SOCl}_2} \text{Benzene} \xrightarrow{\text{AlCl}_3} (B) \] \[ \text{HCN} \xrightarrow{\text{(C)}} \text{HOH} \xrightarrow{\text{H}_2\text{O}} (D) \] The structure of \( D \) would be:

What will be the final product in the following reaction sequence: \[ \text{CH}_3\text{CH}_2\text{CN} \xrightarrow{\text{H}^+ / \text{H}_2\text{O}} A \xrightarrow{\text{NH}_3} B \xrightarrow{\text{NaOBR}} C \]

Keto-enol tautomerism is observed in:

The increasing order for the values of e/m (charge/mass) is:

The half-life of a reaction is inversely proportional to the square of the initial concentration of the reactant. Then the order of the reaction is:

The total number of possible isomers for square-planar \( \text{[Pt(Cl)(NO}_2)(NO_3)(SCN)]^{2-} \) is:

For the reaction, \[ 2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g), \] \[ \Delta H = -57.2 \, \text{kJ/mol} \quad \text{and} \quad K_c = 1.7 \times 10^{16} \] Which of the following statement is INCORRECT?

In which of the following pairs both the ions are coloured in aqueous solutions?

To deposit 0.634 g of copper by electrolysis of aqueous cupric sulphate solution, the amount of electricity required (in coulombs) is:

What is the product of the following reaction?
Hex-3-ynal + (i) NaBH\(_4\), (ii) Pb\(_3\), (iii) Mg/ether, (iv) CO\(_2\)/H\(_2\)O → ?

Which of the following reactions can produce aniline as the main product?

In the following sequence of reactions, \[ \text{CH}_3\text{CH}_2\text{OH} \xrightarrow{P_1,2} A \xrightarrow{\text{Mg/ether}} B \xrightarrow{\text{HCHO}} C \xrightarrow{H_2O} D \] The compound D is:

Secondary structure of protein refers to:

In the following skew conformation of ethane, the \( H' - C - C - H'' \) dihedral angle is:

Xenon hexafluoride on partial hydrolysis produces compounds 'X' and 'Y'. Compounds 'X', 'Y' and the oxidation state of Xe are respectively:

Consider the following statements: I. Increase in concentration of reactant increases the rate of a zero order reaction. II. Rate constant \( k \) is equal to collision frequency if \( E_a = 0 \). III. Rate constant \( k \) is equal to collision frequency if \( E_a = \infty \). IV. \( \ln k \) vs \( T \) is a straight line. V. \( 1/T \) vs \( \ln k \) is a straight line. Correct statements are:

Consider the following reactions: \[ \text{NaCl} + \text{K}_2\text{Cr}_2\text{O}_7 + \text{H}_2\text{SO}_4 (\text{Conc.}) \rightarrow (A) + \text{Side products} \] \[ (B) + \text{H}_2\text{SO}_4 (\text{dilute}) + \text{H}_2\text{O}_2 \rightarrow (C) + \text{Side products} \] The sum of the total number of atoms in one molecule each of (A), (B) and (C) is __________.

The edge length of unit cell of a metal having molecular weight 75 g/mol is 5 Å which crystallizes in cubic lattice. If the density is 2 g/cc, then find the radius of the metal atom. (\( N_A = 6 \times 10^{23} \)) Give the answer in pm.