List of top Chemistry Questions

The energy of an electron in the $3\,S$ orbital (excited state) of $H$ - atom is

The coordination number and oxidation state of ( in $K_3[Cr(C_2O_4)_3]$ are respectively

Which of the following is the correct unit of angular momentum of an lectron in an orbital of an atom?

At anode in the electrolysis of fused sodium chloride

Choose the correct statement from the following which is related to electrochemical series

Which one of the following is correct decreasing order of acidity?

In a Galvanic cell

$23\, g$ of ethanol $(C_2H_5OH)$ on reaction with ethanoic acid $(CH_3COOH)$ forms $44\, g$ of ethyl ethanoate $(CH_3COOC_2H_5)$ and some weight of water. The percentage yield of the reaction is

Among the following, which species represents a pseudohalide?

$ A(g)+3B(g)4C(g) $ Initially concentration of $ A $ is equal to that of $ B $ . The equilibrium concentrations of $ A $ and $ C $ are equal. $ {{K}_{c}} $ is:

The basicity of pyrophosphorous acid is

An alkene $ {{C}_{4}}{{H}_{8}} $ , was treated with ozone and then with zinc and water to give acetone and formaldehyde. The alkene is:

The time required for 10% completion of a first order reaction at 298 K is equal to that required for its 25% completion at 308 K. If the value of A is \(4 \times 10^{10} s^{-1}\) . Calculate \(k\) at 318 K and \(E_a\).

The oxidation number of cobalt in \(K[Co(CO)_4]\) is

The following data were obtained during the first order thermal decomposition of \(SO_2Cl_2\) at a constant volume.
\(SO_2Cl_2(g) → SO_2(g) + Cl_2(g)\)

Experiment	Time/s-1	Total pressure/atm
1	0	0.5
2	100	0.6

Calculate the rate of the reaction when total pressure is 0.65 atm.

Predict the products of electrolysis in each of the following: 
 (i) An aqueous solution of AgNO₃ with silver electrodes. 
 (ii) An aqueous solution of AgNO₃ with platinum electrodes. 
 (iii) A dilute solution of H₂SO₄ with platinum electrodes. 
 (iv) An aqueous solution of CuCl₂ with platinum electrodes.

Syngas is a mixture of

Reaction of diborane with ammonia gives initially

A binary solid has a primitive cubical structure with $B^-$ ions constituting the lattice points and $A^+$ ions occupying $25\%$ of its tetrahedral holes. The molecular formula of the crystal is

Among the following, the optically active compound is

Sphalerite is concentrated by

$1.5\, g$ of a non-volatile, non-electrolyte is dissolved in $50 \,g$ benzene $(K_b\, =\, 2.5\, K kg \,mol^{-1}$ ). The elevation of the boiling point of the solution is $0.75\, K$. The molecular weight of the solute in $g$ $mol^{-1}$ is

IUPAC name of $ C{{H}_{3}}CH=\underset{\begin{align} & | \\ & C{{H}_{2}} \\ & | \\ & C{{H}_{3}} \\ \end{align}}{\mathop{C}}\,C{{H}_{3}} $

An atom with high electronegativity has

Ammonium ion $\left( NH _{4}^{+}\right)$ reacts with nitrite ion $\left( NO _{2}^{-}\right)$ in aqueous solution according to the equation $NH _{4}^{+}(a q)+ NO _{2}^{-}(a q) \longrightarrow N _{2}(g)+2 H _{2} O (l)$ The following initial rates of reaction have been measured for the given reactant concentrations. Which of the following is the rate law for this reaction?