List of top Chemistry Questions

The correct order of nucleophilicity is

Manganese (VI) has ability to disproportionate in acidic solution. The difference in oxidation states of two ions it forms in acidic solution is _____.

Which one of the following alkaline earth metal ions has the highest ionic mobility in its aqueous solution?

Low oxidation state of metals in their complexes are common when ligands :

An element M crystallises in a body centred cubic unit cell with a cell edge of 300 pm. The density of the element is 6.0 g cm^–3. The number of atoms present in 180 g of the element is ______× 10²³. (Nearest integer)

Which anion will be formed when ethyl 3-oxobutanate is treated with alkali?

For a reaction, the rate constant K. is expressed as log₁₀ K=14.2-C/T. Activation energy of the reaction is

Consider the above reaction; which one of the following compounds does not produce acetanilide from aniline?

The Product 'A' is

This compound has both ionic and covalent bonds:

\(2\) \(mol\) of \(Hg(g)\) is combusted in a fixed volume bomb calorimeter with excess of \(O_2\) at 298K and 1 atm into \(HgO(s)\) During the reaction, temperature increases from \(2980\) \(K\) to \(3128\) \(K\). If heat capacity of the bomb calorimeter and enthalpy of formation of \(Hg(g)\) are \(2000\) \(kJ \;K^{-1}\) and \(6132\) \(kJ \;mol^{-1}\) at \(298\) \(K\), respectively, the calculated standard molar enthalpy of formation of \(HgO(s)\) at \(298\) \(K\) is \(X\) \(kJ \;mol^{-1}\) The value of | \(X\) | is [Given : Gas constant \(R\) =\(83\) \(J\) \(K^{-1}\) \(mol^{-1}\)] 

The treatment of an aqueous solution of $3.74\, g$ of $Cu \left( NO _3\right)_2$ with excess $KI $ results in a brown solution along with the formation of a precipitate.Passing $H _2 S$ through this brown solution gives another precipitate $X$ The amount of $X$ (in $g$ ) is ___ . [Given : Atomic mass of $H =1, N =14, O =16, S =32, K =39, Cu =63, I =127$ ]

A solution is prepared by mixing $0.01\, mol$ each of $H _2 CO _3, NaHCO _3, Na _2 CO _3$, and $NaOH$ in $100 \, mL$ of water $pH$ of the resulting solution is ___ [Given : $p K _{ a 1}$ and $p K _{ a 2}$ of $H _2 CO _3$ are $637$ and $1032$, respectively $; \log 2=030$ ]

The reaction of $HClO _3$ with $HCl$ gives a paramagnetic gas, which upon reaction with $O _3$ produces

The correct option(s) related to the extraction of iron from its ore in the blast furnace operating in the temperature range $900-1500 K$ is(are)

2 mol of Hg(g) is combusted in a fixed volume bomb calorimeter with excess of O₂ at 298 K and 1 atm into HgO(s). During the reaction, temperature increases from 298.0 K to 312.8 K. If heat capacity of the bomb calorimeter and enthalpy of formation of Hg(g) are 20.00 kJ K^–1 and 61.32 kJ mol^–1 at 298 K, respectively, the calculated standard molar enthalpy of formation of HgO(s) at 298 K is X kJ mol^–1. The value of |X| is _______.
[Given: Gas constant R = 8.3 J K^–1 mol^–1]

Which of the following is not a conductor?

Which of the following is (are) stronger acid than acetic acid ?

For complex compounds, the correct statements are:
(A) Number of unpaired electrons of both tetrahedral and octahedral complexes depends on the nature of the ligands.
 (B) In general, copper (II) and zinc (II) display coloured and colourless complex compounds, respectively.
 (C) Shape of co-ordination compounds does not depend on the hybridization of the central metal.
 (D) Nickel (II) complexes show diamagnetic and paramagnetic behaviour in square planer and octahedral structures, respectively.

Select the chemicals which can act as nucleophile.

Which of the following compounds can exhibit geometrical isomerism ?

For a, ẞ and y rays, the incorrect order/s is/are