List of top Chemistry Questions

Calamine is an ore of which of the following ?
The red colouring pigment Haemoglobin in our blood contains which metal ?
Natural Rubber obtained from Rubber tree is basically a polymer of :
The metal most commonly used for making filament of an electric bulb is :
Which was the first organic compound synthesized in the laboratory ?
Which of the following is a member of the Halogen family ?
When water is poured over sodium peroxide, which colourless gas is produced ?
The most abundant gas found in the earth atmosphere is :
Select from the following a set of three metals which are found in free state :
Which of the following is the most electronegative element in the periodic table ?
The gas which may cause explosion in coal mines is :
During summer, water kept in an earthern pot becomes cool because of the phenomenon of :
A gel toothpaste is a mixture of a :
The Chemical symbol for tin is :
The compound that can be purified by sublimation is :
A 100 mL flask contained \(H_2\) at 200 torr, and a 200 mL flask contained \(He\) at 100 torr. The two flask were then connected so that each gas filled their combined volume. Assume, no change in temperature, total pressure is
Hydrogen peroxide oxidises $[Fe(CN)6]^{4-}$ to $[Fe(CN)6]^{3-}$ in acidic medium but reduces $[Fe(CN)6]^{3-}$ to$[Fe(CN)6]^{4-}$ in alkaline medium. The other products formed are, respectively
Two compounds I and II are eluted by column chromatography (adsorption of I > II). Which one of following is a correct statement ?
When $9.65\,A$ current was passed for $1.0\, hour$ into nitrobenzene in acidic medium, the amount of p-aminophenol produced is_____.
Which of the following molecules represents the order of hybridisation sp2 , sp2 , sp, sp from left to right atoms ?
If molar conductivity of \(Ca^{2+}\) and \(Cl^-\) ions are 119 and 71 Scm2 mol-1 respectivily, then the molar conductivity of \(CaCl_2\) at infinite dilution is
pH of a $0.1\, M$ monobasic acid is found to be $2$. Hence, its osmotic pressure at a given temperature $TK$ is
Following are colours shown by some alkaline earth metals in flame test. Which of the following are not correctly matched?
Amongst the elements with following electronic configurations, which one of them may have the highest ionization energy?
The rate constant of a reaction is $1.5 \times 10^{-3}$ at $25^{\circ} C$ and $2.1 \times 10^{-2}$ at $60^{\circ} C$. The activation energy is