List of top Chemistry Questions

Which of the following does not evolve \( O_2 \) when made to react with water?
Among the oxides SiO\(_2\), SO\(_2\), Al\(_2\)O\(_3\), and P\(_2\)O\(_5\), the correct order of acidic strength is:
Observe the following reaction: \[ xI^- + y \, \, MnO_4^- + z \, H^+ \rightarrow a \, Mn^{2+} + b \, H_2O + cl_2 \] Which of the following are correct?
A crystal is formed by X (cations) and Y (anions). Atoms of Y form ccp and atoms of X occupy half of octahedral voids and half of tetrahedral voids. What is the molecular formula of the crystal?
An alkene ‘X’ (C\(_4\)H\(_8\)) does not exhibit cis/trans isomerism. Reaction of ‘X’ with Br\(_2\)/CCL\(_4\), followed by reaction with reagent ‘Y’ gave ‘Z’ (C\(_6\)H\(_6\)). What are ‘Y’ and ‘Z’ respectively?
Distilled water boils at 373.15 K and freezes at 273.15 K. A solution of glucose in distilled water boils at 373.202 K. What is the freezing point (in K) of the same solution? (For water, \( K_b = 0.52 \) kg mol\(^{-1}\), \( K_f = 1.86 \) kg mol\(^{-1}\))

The set of elements which obey the general electronic configuration \( (n-1)d^{10} ns^2 \) is:}

Observe the following species: (i) \( NH_3 \) (ii) \( AlCl_3 \) (iii) \( SnCl_4 \) (iv) \( CO_2 \) (v) \( Ag^+ \) (vi) \( HSO_4^- \) How many of the above species act as Lewis acids?
Kaolinite is a silicate mineral of metal 'X' and calamine is a carbonate mineral of metal 'Y'. X and Y respectively are:
The wavenumber of the first spectral line of the Lyman series of He\(^+\) ion is \( x \) m\(^{-1}\). What is the wavenumber (in m\(^{-1}\)) of the second spectral line of the Balmer series of Li\(^{2+}\) ion?
An open vessel containing air was heated from 27°C to 727°C. Some air was expelled. What is the fraction of air remaining in the vessel? (Assume air as an ideal gas)
Identify the correct statements from the following: (i) Ti (IV) is more stable than Ti (III) and Ti (II)
(ii) Among 3d-series elements (from Z = 22 to 29) only copper has positive reduction potential (\( M^{2+}/M \)) (iii) Both Sc and Zn exhibit +1 oxidation state
Electromagnetic radiation has electric and magnetic field components. These two components:
The common components of photochemical smog are:
At T(K), \( K_c \) for the dissociation of \( PCl_5 \) is \( 2 \times 10^{-2} \) mol L\(^{-1}\). The number of moles of \( PCl_5 \) that must be taken in 1.0 L flask at the same temperature to get 0.2 mol of chlorine at equilibrium is
Two statements are given below. Statement I: Adsorption of a gas on the surface of charcoal is primarily an exothermic process.
Statement II: A closed vessel containing \( O_2(g) \), \( H_2(g) \), \( Cl_2(g) \), \( NH_3(g) \) has a pressure of 9 atm. About 1 g of charcoal was added to this vessel and after some time its pressure is \( P' \) atm. It is observed that \( P'>P \). Choose the correct answer.
The oxygen carrying capacity of blood is reduced due to binding of haemoglobin with
In the following reaction: \[ \text{C} + \text{Conc.} \, \text{H}_2\text{SO}_4 \xrightarrow{\Delta} \text{X} + \text{Y} + \text{H}_2\text{O} \] X and Y in the above reaction are:
Which of the following is used as a substitute for sucrose?
At 300 K, the vapour pressure of liquids A and B are 600 and 500 mm of Hg respectively. Two moles of A and three moles of B are mixed. The mole fractions of A and B in vapor state are respectively
Among the following, the incorrect statement about chloramphenicol is:
The technique used to purify an organic compound present in aqueous medium and which is less soluble in organic solvent is
In the following reaction sequence, what are X and Y respectively?
nucleophilic addition of a methoxy group

The correct order of boiling points of hydrogen halides is: 

The normality of a 20-volume solution of hydrogen peroxide is: