List of top Chemistry Questions

For a reaction, the half-life is independent of initial concentration. What is the order of that reaction?

For a first order reaction, $(A)\to $ product. Concentration of $A$, changes from $0.1\, M$ to $0.025 \,M$ in $40$ minutes the rate of reaction of when concentration of $A$ is $0.01 \,M$ is :

Unit of the constant of zero order reaction is:

The half - life of a radioisotope is four hours. If the initial mass of the isotope was 200 g, the mass remaining after 24 hours undecayed is

A gas has a vapour density $11.2.$ The volume occupied by $lg$ of the gas at NTP is :

To neutralize completely $20 \,mL$ of $0.1\, M$ aqueous solution of phosphorous acid $(H_3PO_3)$, the volume of $0.1\, M$ aqueous $KOH$ solution required is

On reduction with hydrogen, $3.6 \,g$ of an oxide of metal left $3.2 \,g $ of metal. If the vapour density of metal is $32$ , the simplest formula of the oxide would be :

The ammonia evolved from the treatment of 0.30 g of an organic compound for the estimation of nitrogen was passed in 100 mL of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5 M sodium hydroxide solution hydroxide solutio for complete neutralization. The organic compound is

The significant figure in 3400 are

Specific conductivity of a solution

The conjugate acid of $NH_{3}$ ion is:

Dimethyl glyoxime gives a red precipitate with $Ni ^{2+}$, which is used for its detection. To get this precipitate readily the best $pH$ range is

For the reaction, $ {CO(g) + Cl2(g) <=> COCl2(g)}$ the $\frac{K_{p}}{K_{c}}$ is equal to

What is the equilibrium expression for the reaction $ {P_{4(s)} +5O_{2(g)} <=> P4O_{10(s)}}$ ?

The solubility product of $Ag _{2} CrO _{4}$ is $32 \times 10^{-12}$. What is the concentration of $CrO _{4}^{2-}$ ions in that solution (in $g$ ions $\left.L^{-1}\right)$ ?

Among the following the dissociation constant is highest for

Which of the following is not considered as an organometallic compound?

$o- $Toluic acid on reaction with $Br _{2}+ Fe$ gives

The monomer of nylon-6 is/are :

Which of the following is not a protein?

The statement true for $N_3^-$ is

The smog is essentially caused by the presence of

The reagent used for the separation of acetaldehyde from acetophenone is

The coordination number of a central metal atom in a complex is determined by

Select the $pK_a$ value of the strongest acid from the following :