List of top Chemistry Questions

Electromagnetic radiation of wavelength 663 nm is just sufficient to ionise the atom of metal A. The ionization energy of metal A in kJ mol⁻¹ is ________ . (Rounded-off to the nearest integer) [h=6.63$\times$10⁻³⁴ Js, c=3.00$\times$10⁸ ms⁻¹, N$_A$=6.02$\times$10²³ mol⁻¹]
Among the following, number of metal/s which can be used as electrodes in the photoelectric cell is ________ . (Integer answer)
(A) Li (B) Na (C) Rb (D) Cs
Consider titration of NaOH solution versus 1.25 M oxalic acid solution. At the end point following burette readings were obtained. (i) 4.5 mL, (ii) 4.5 mL, (iii) 4.4 mL, (iv) 4.4 mL, (v) 4.4 mL. If the volume of oxalic acid taken was 10.0 mL then the molarity of the NaOH solution is _______ M. (Rounded-off to the nearest integer)
The unit cell of copper corresponds to a face centered cube of edge length 3.596 Å with one copper atom at each lattice point. The calculated density of copper in kg/m³ is ________ . [Molar mass of Cu: 63.54 g; Avogadro Number=6.022$\times$10²³]
What is 'X' in the given reaction?
CH$_2$OH—CH$_2$OH + oxalic acid $\xrightarrow{210^\circ\text{C}}$ X (major product)
The major product of the following reaction is :
CH$_3$CH$_2$CH=CH$_2$ + H$_2$/CO $\xrightarrow{\text{Rh catalyst}}$
Which of the following compound is added to the sodium extract before addition of silver nitrate for testing of halogens?
Given below are two statements:
Statement I: The pH of rain water is normally ~5.6.
Statement II: If the pH of rain water drops below 5.6, it is called acid rain.
The correct order of bond dissociation enthalpy is:
The set of elements that are used in the fabrication of transistors is:
The method used for the purification of Indium is:
Given below are two statements:
Statement I: $\alpha$ and $\beta$ forms of sulphur can change reversibly between themselves with slow heating or slow cooling.
Statement II: At room temperature the stable crystalline form of sulphur is monoclinic sulphur.
Water does not produce CO on reacting with:
Which one of the following statements is FALSE for hydrophilic sols?
The solubility of Ca(OH)$_2$ in water is:
[Given: The solubility product of Ca(OH)$_2$ in water = 5.5 $\times$ 10⁻⁶]
The pH of a solution obtained by mixing 50 mL of 1 M HCl and 30 mL of 1 M NaOH is $x \times 10^{-1}$. The value of $x$ is ________. (Nearest integer) [log 2.5 = 0.3979]
$\text{CH}_4$ is adsorbed on 1 g charcoal at $0^\circ\text{C}$ following the Freundlich adsorption isotherm. 10.0 mL of $\text{CH}_4$ is adsorbed at 100 mm of Hg, whereas 15.0 mL is adsorbed at 200 mm of Hg. The volume of $\text{CH}_4$ adsorbed at 300 mm of Hg is $10^x$ mL. The value of $x$ is ________ $\times 10^{-2}$. (Nearest integer) [Use $\log_{10} 2 = 0.3010, \log_{10} 3 = 0.4771$]
1.22 g of an organic acid is separately dissolved in 100 g of benzene ($K_b = 2.6 \text{ K kg mol}^{-1}$) and 100 g of acetone ($K_b = 1.7 \text{ K kg mol}^{-1}$). The acid is known to dimerize in benzene but remain as a monomer in acetone. The boiling point of the solution in acetone increases by $0.17^\circ\text{C}$. The increase in boiling point of solution in benzene in $^\circ\text{C}$ is $x \times 10^{-2}$. The value of $x$ is ________. (Nearest integer) [Atomic mass : C = 12.0, H = 1.0, O = 16.0]
The empirical formula for a compound with a cubic close packed arrangement of anions and with cations occupying all the octahedral sites is $A_x B$. The value of $x$ is ________. (Integer answer)
The value of magnetic quantum number of the outermost electron of $\text{Zn}^+$ ion is ________. (Integer answer)
In the electrolytic refining of blister copper, the total number of main impurities, from the following, removed as anode mud is ________.
Pb, Sb, Se, Te, Ru, Ag, Au and Pt.
Which among the following is not a polyester ?
The deposition of X and Y on ground surfaces is referred as wet and dry depositions, respectively. X and Y are :
In which one of the following sets all species show disproportionation reaction ?
Which one of the following statements is incorrect?