List of top Chemistry Questions

Which of the following species is paramagnetic in nature ?

Which of the following species is an electrophile ?

Which of the following is the correct order of acidity of carboxylic acids? $(i) Cl_{3}CCOOH >\, Cl_{2}CHCOOH >\, ClCH_{2}COOH$ $(ii) CH_{3}CH_{2}COOH >\, (CH_{3})_{2} CHCOOH >\, (CH_{3})_{3} CCOOH$ (iii) $F_{2}CHCOOH >\, FCH_{2}COOH > \,ClCH_{2}COOH$

Which of the following is the correct $IUPAC$ name?

Which of the following is/are alicyclic heterocyclic compound ?

Which of the following is an example of elimination reaction ?

Which of the following is an aromatic heterocyclic compound ?

Which of the following intermediates contains three pairs of electrons in its valence shell?

Which of the following has + R (resonance) effect ?

Which of the following has maximum acidic strength ?

Which of the following group has the maximum hyperconjugation effect ?

Lassaigne?? test for the detection of nitrogen fails in

Degree of dissociation of an acid HCl is 95% 0.192 g of the acid is present in 0.5 L of solution.The pH of the solution is

Equilibrium constant, K changes with temperature. At 300 K, equilibrium constant is 25 and at 400 K it is 10. Hence, backward reaction will have energy of activation

Equimolar concentrations of $H_2$ and $I_2$ are heated to equilibrium in a 2 litres flask. At equilibrium, the forward and the backward rate constants are found to be equal. What percentage of initial concentration of $H_2$ has reacted at equilibrium ?

For a polybasic acid, the dissociation constants have a different values for each step, e.g., $ {H3A <=> H+ +H2A^-}$ ; $K=K_{a_1}$ $ {H2A- <=> H+ +H2A^{2-}}$ ; $K=K_{a_2}$ $ {HA^{2-} <=> H+ +A^{3-}}$ ; $K=K_{a_3}$ What is the observed trend of dissociation constants in successive stages?

For preparing a buffer solution of pH 6 by mixing sodium acetate and acetic acid, the ratio of the concentration of salt and acid should be $(K_a= 10^{-5})$

For the gas phase reaction $ {2NO<=>N2 +O2}$ $?H = - 43.5 \,kcal\, mol^{-1}$ which one of the statements below is true for $ {N_{2(g)} +O_{2(g)} <=> 2NO_{(g)}}$

For the reaction $ {2NO_{2(g)} <=> N2O_{4(g)}, K_{p}/K_{c}}$ is equal to

For the reaction : $ {H2_{(g)} +I2_{(g)} <=> 2HI_{(g)}}$, the standard free energy is $\Delta G^{\circ} > 0$. The equilibrium constant $(K)$ would be________.

Formation of $ClF_3$ from $Cl_2$ and $F_2$ is an exothermic process. The equilibrium system can be represented as $ {Cl2_{(g)} +3F2_{(g)}<=>2ClF3}$ ; $\Delta H=-329\,kj\,mol^{-1}$ Which of the following will increase quantity of $ClF_3$ in the equilibrium mixture?

How many gram equivalents of NaOH are required to neutralize 25 $cm^3$ of decinormal HCl solution ?

If $K_{sp}$ of $Mg(OH)_2$ is $1.2 ? 10^{-11}$. Then the highest pH of the $0.1\, M$ solution of $Mg^{2+}$ ion from which $Mg(OH)_2$ is not precipitated is

If pH of a solution decreases from 5 to 2, then it is

If $S_1, S_2, S_3$ and $S_4$ are the solubilities of $AgCl$ in water, in $0.01\, M\, CaCl_2$, in $0.01\, M\, NaCl$ and in $0.05\, M\, AgNO_3$ respectively at a certain temperature, the correct order of solubilities is