List of top Chemistry Questions

A pressure cooker reduces cooking time for food because :

The shape of a molecule of NH$_3$, in which the central atom contains a lone pair of electrons, is

The rate constant of a reaction at temperature 200 K is 10 times less than the rate constant at 400 K. What is the activation energy $ E_a$ of the reaction? (R = Gas constant)

The pyknometric density of sodium chloride crystal is 2.165×10³ kg m^–3 while its X-ray density is 2.178×10³ kg m^–3. The fraction of unoccupied sites in sodium chloride crystal is:

Which one of the following octahedral complexes will not show geometric isomerism? (A and B are monodentate ligands)

The number of unpaired electrons in the complex ion \([CoF_6]^{3–}\) is: (Atomic No.of Co = 27) 

Which one of the following characteristics of the transition metals is associated with their catalytic activity:

For the reaction: \(C_3H_8(g)+5O_2(g)→3CO_2(g)+4H_2O(l)\) at constant temperature, ∆H–∆E is:

Which of the following statements is not correct for sigma and pi-bonds formed between two carbon atoms:

Which one of the following compounds is not a protonic acid:

Which of the following possesses highest melting point?

$H_3BO_3$ is

Which has maximum number of atoms?

The most reactive nucleophile among the following is

An asymmetric carbon atom is that in which

What would be the freezing point of aqueous solution containing $17\, g$ of $C _{2} H _{5} OH$ in $1000\, g$ of water?

Azeotropic mixture of $ HCl $ and water has:

The ionic strength of a solution containing 0.1 mole/kg of KCl and 0.2 mole/kg of $CuSO_4$ is

What is the effect of dilution on the equivalent conductance of strong electrolyte?

In first order reaction, the concentration of reactant decreases from $800\, mol\, cm ^{-3}$ to $50\, mol\, cm ^{-3}$ in $2 \times 10^{4} s$. The rate constant is

Volume of $ C{{O}_{2}} $ obtained from complete decomposition of $ 20\,\,g\,\,CaC{{O}_{3}} $ at STP is:

When potassium dichromate crystals are heated, we get

Which one of the following metal is used in galvanization?

Which of the following are isoelectronic and isostructural ? $NO_3^-$, $CO_3^{2-}$, $ClO_3^{-}$, $SO_3$

The correct order of stability of carbocations, is: