List of top Chemistry Questions

One mole of hydrazine $(N_2H_4)$ loses $10$ moles of electrons in a reaction to form a new compound $X$. Assuming that all the nitrogen atoms in hydrazine appear in the new compound, what is the oxidation state of nitrogen in $X$ ? (Note: There is no change in the oxidation state of hydrogen in the reaction)

Narcotic analgesic is

Which one of the following is a benzenoid aromatic compound?

One of the builders present in scouring soaps?

The hybridisation of $C$ in diamond, graphite and ethyne is in the order

Which reaction is not appropriate for the synthesis of the following?

The spin-only magnetic moment of $\left[crF_{6}\right]^{4-}$ (atomic number of Cr is 24) is

The structure of $XeF_2$ and $NH_3$ respectively are

$ DDT $ is

The rate constant of the reaction $2N_2O_5 \rightarrow 4NO_2 + O_2$ at $300\,K$ is $3 \times 10^{-5}\,s^{-1}$. If the rate of the reaction at the same temperature is $2.4 \times 10^{-5}\, mol\, dm^{-3}\, s^{-1}$, then the molar concentration of $N_2O_5$ is

The degree of dissociation $(\alpha)$ of a weak electrolyte $A_xB_y$ is related to van?t Hoff factor $(i)$ by the expression

If glucose of $36\, g$ weight is dissolved in $2 \,kg$ of $H_2O$ then, change in boiling point $(\Delta T_b)$ at 1.013 bar will be ($K_b$ for ${H_2O}$ is ${ 0.52\, K\, kg \,mol^{-1}}$)

Concentrated aqueous sulphuric acid is $98 \% \,H _{2} SO _{4}$ by mass and has a density of $1.80 \,g .\, mL ^{-1}$ Volume of acid required to make $1$ litre of $0.1\, M \,H _{2} SO _{4}$ solution is:

With increase in temperature, which one of these changes?

In the plot of $ PV $ vs $ P $ at $ 273\, K $ , positive deviation from ideal behaviour under all pressure conditions is shown by the gas

In a first order reaction, the time taken for 90% decay is 12 days. The time taken for 99% decay is

Thermal decomposition of $HI$ on gold surface is a

The overall order of a reaction which has the rate expression, rate = $k[A]^{1/2}\, [B]^{1/2}$ is

For a 1st order reaction the unit of rate constant is

Inversion of cane sugar by acid hydrolysis in excess of water is

$ 50\% $ of a first order reaction is complete in $ 23 $ minutes. Calculate the time required to complete $ 90\% $ of the reaction

75% of a first order reaction was completed in 32 min. When would 50% of the reaction completed?

The half life period of a radio active element is $30$ days, after $90$ days the following quantity will be left

What weight of $ HCl $ is present in $ 155\, ml $ of a $ 0.54\, M $ solution?