List of top Chemistry Questions

Which one is not paramagnetic among the following? [at. no. of $Be = 4, N e = 10$ , $A s= 33,Cl= 17$]

The number of antibonding electron pairs in $O_2^{2-}$ molecular ion on the basis of molecular orbital theory is (at. no. of $O$ is $18$)

Which one of the following elements constitutes a major impurity in pig iron?

The total number of possible isomers for the complex compound $[Cu^{II}(NH_3)_4] [Pt^{II}Cl_4] $ are

Glucose reacts with X number of molecules of phenyl hydrazine to yield osazone. The value of $ X $ is

The enormous diversity of protein molecules is due mainly to the diversity of

Which of the following compounds is not chiral ?

A one litre flask is full of brown bromine vapours. The intensity of brown colour of vapours will not decrease appreciably on adding to the flask some

In $ PO_{4}^{3-} $ ion, the formal charge on each oxygen atom and $P-O$ bond order respectively are :

The standard reduction potentials at 298 K for the following half cell reactions are given below: $ Z{{n}^{2+}}(aq)+2{{e}^{-}}\rightleftharpoons Zn(s)-0.762 $ $ C{{r}^{3+}}(aq)+3{{e}^{-}}\rightleftharpoons Cr(s)-0.74 $ $ 2{{H}^{+}}(aq)+2{{e}^{-}}\rightleftharpoons {{H}_{2}}(g)\,0.00 $ $ F{{e}^{3+}}(aq)+{{e}^{-}}\rightleftharpoons F{{e}^{2+}}(aq)+0.77 $ Which one of the following is the strongest reducing agent?

The radii of $ \text{F,}{{\text{F}}^{-}}\text{O} $ and $ {{\text{O}}^{2-}} $ are in the order

The state of hybridization of B in $ \text{BC}{{\text{l}}_{\text{3}}} $ is :

The first emission line in the atomic spectrum of hydrogen in the Balmer series appears at:

The activity of ratio altitude $ ({{X}^{100}}) $ is 6.023 curie. If its disintegration constant is $ 3.7\times {{10}^{4}}{{\sec }^{-1}}, $ the mass of X is :

Hydrogen bonding is not present

The richest source of vitamin A are:

Highly pure dilute solution of sodium in liquid ammonia

Which of the following salt has the same value of vant?s Hoff factor as that of $K _{3}\left[ Fe ( CN )_{6}\right]$ ?

The freezing point of a solution prepared from 1.25 g of non-electrolyte and 20 g of water is 271.9K. If molar depression constant is 1 86 $K m^{-1}$ then molar mass of the solute will be

The solubility of $BaSO_4$ in water is $2.33 \times 10^{-3}$ gram/litre. Its solubility product will be (molecular weight of $BaSO_4 = 233$)

Which of the following has highest boiling point?

For the first order reaction,

A first order reaction, which is $30\%$ complete in $30$ minutes has a half-life period of

For the reaction A$\to$ B, the rate law expression is rate = k [A], Which of the following statements is incorrect ?

The rate constant of reaction is $0.69 \times 10^{-2} min ^{-1}$ and the initial concentration is $0.2\, mol L ^{-1}$. The half-life period is