List of top Chemistry Questions asked in KEAM

The molecule with the highest dipole moment among the following is
The molar entropy of which of the following reaction is negative?
Which of the following substance has the standard molar enthalpy of formation zero?
A certain amount of H$_{2(g)}$ and I$_{2(g)}$ are sealed in a 4L container and kept at 600K to attain equilibrium. K$_C$ for the reaction, H$_{2(g)}$ + I$_{2(g)} \rightleftharpoons$ 2HI\(_{(g)}\) at 600K is 64. If the equilibrium concentration of HI\(_{(g)}\) is 0.08M, what are the equilibrium concentrations of H$_{2(g)}$ and I$_{2(g)}$ at the same temperature?
List-I contains some group-I elements and List-II contains their electron gain enthalpy values (in kJ mol\(^{-1}\))
List-I: (i) H, (ii) Li, (iii) Na, (iv) K
List-II: (a) -48, (b) -53, (c) -73, (d) -60
Choose the correct match.
The covalent bond length is almost the same in which of the following pairs of bonds
2.8 g of N$_{2(g)}$ and 0.8 g of H$_{2(g)}$ are allowed to react completely. What is the mass of NH$_{3(g)}$ formed? (molar mass of N$_{2(g)}$=28, H$_{2(g)}$=2 and NH$_{3(g)}$=17)}
According to Bohr's theory the radius of the second stationary state of hydrogen atom is
The correct decreasing order of the first ionization enthalpies among the elements C, N, O, F is
Consider the following statements about photoelectric effect:
(i) There is time lag between the striking of light beam and the ejection of electrons from the metal surface.
(ii) The number of electrons ejected is directly proportional to the intensity or brightness of light.
(iii) For each metal, there is a characteristic minimum frequency, known as threshold frequency (\(\nu_0\)) below which photoelectric effect is not observed.
(iv) At a frequency greater than \(\nu_0\), the ejected electrons come out with certain kinetic energy. The kinetic energies of these electrons increase with the increase of the wavelength of the light used.
Which of the above statements are true?
The descending order of basic strength of the following amines is
(i) N-Methylbenzenamine (ii) N,N'-Dimethylbenzenamine (iii) Benzenamine (iv) Phenylmethanamine
Benzene diazonium chloride on treatment with HCl in the presence of copper powder gives chlorobenzene. This reaction is termed as
Vigorous oxidation of n-propylbenzene with alkaline potassium permanganate ($\mathrm{KMnO_4/KOH/\Delta}$) followed by hydrolysis gives
Which of the following is a commercial method of manufacture of benzaldehyde?
When 2-methylbutan-2-ol is treated with Lucas reagent (conc. HCl and $\mathrm{ZnCl_2}$) at room temperature, the product obtained is
The relative ease of dehydration of the following alcohols is
(i) Propan-2-ol (ii) Propan-1-ol (iii) 2-Methylpropan-2-ol
The formula of pentaamminecarbonatocobalt(III) chloride is
Which of the following gives 2-methylbutane on hydrogenation?
(i) 2-methylbut-1-ene (ii) 3-methylbut-1-yne (iii) 2-methylbut-2-ene
(iv) 3-methylbut-1-ene (v) pent-2-ene
The correct increasing order of wavelength of absorption of the following complexes is
(i) \([\mathrm{CoCl(NH_3)_5}]^{2+}\) (ii) \([\mathrm{Co(NH_3)_5(H_2O)}]^{3+}\) (iii) \([\mathrm{Co(NH_3)_6}]^{3+}\) (iv) \([\mathrm{Co(CN)_6}]^{3-}\)
An alkene, \(\mathrm{C_3H_6}\) (X), on treatment with HBr in presence of peroxide gives (Y). The compound (Y) on treatment with \(\mathrm{AgNO_2}\) in ethanol gives (Z). The compounds (X), (Y) and (Z) are respectively
When sodium fusion extract is treated with sodium nitroprusside, the appearance of violet colour is due to the formation of
The reaction \(\mathrm{CH_3Br + AgF \rightarrow CH_3F + AgBr}\) is termed as
Which of the following compound of manganese is a mixed oxide?
The molar conductivity of a weak monobasic acid, HA at 298 K is \(70\ \text{S cm}^2\text{ mol}^{-1}\). What is the percentage ionisation of HA at 298 K?
At infinite dilution \(\lambda^\circ_{H^+} = 340\ \text{S cm}^2\text{ mol}^{-1}\) and \(\lambda^\circ_{A^-} = 80\ \text{S cm}^2\text{ mol}^{-1}\)
The percentage of helium present in air used by scuba divers is