List of top Chemistry Questions

Which one of the following reactions is expected to readily give a hydrocarbon product in good yields?

The number of enantiomers of the compound \( \text{CH}_3 \text{CHBr} \text{CHBrCOOH} \) is

Among the following four structures I to IV, it is true that

The alkali metals form salt-like hydrides by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following orders?

When same amount of zinc is treated separately with excess of sulphuric acid and excess of sodium hydroxide solution, the ratio of volumes of hydrogen evolved is:

For the reaction \( \text{CO(g)} + \frac{1}{2} \text{O}_2 (g) \rightarrow \text{CO}_2 (g) \), \( K_c \) is

The oxidation state of sulphur in \( \text{Na}_2 \text{S}_4 \text{O}_6 \) is

If 1.0 mole of \( \text{I}_2 \) is introduced into a 1.0 litre flask at 1000 K, at equilibrium (\( K_c = 10^{-6} \)), which one is correct?

The enthalpy of combustion of 2 moles of benzene at 27°C differs from the value determined in bomb calorimeter by

Increasing order of rms velocities of \( \text{H}_2 \), \( \text{O}_2 \), \( \text{N}_2 \) and \( \text{HBr} \) is

For the dissociation reaction, \( \text{H}_2 \rightarrow \text{H} + \text{H} \), \( \Delta H = 162 \, \text{Kcal} \), heat of atomisation of H is

Using MOT, which of the following pairs denote paramagnetic species?

When the first ionisation energies are plotted against atomic number, the peaks are occupied by

The screening effect of \( d \)-electrons is

The ions \( \text{O}^{2-} \), \( \text{F}^- \), \( \text{Na}^+ \), \( \text{Mg}^{2+} \) and \( \text{Al}^{3+} \) are isoelectronic. Their ionic radii show:

The Bohr orbit radius for the hydrogen atom (\( n = 1 \)) is approximately 0.530 Å. The radius for the first excited state (\( n = 2 \)) orbit is (in Å)

How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0 M \( \text{HNO}_3 \)? The concentrated acid is 70% \( \text{HNO}_3 \).

In Goldschmidt aluminothermic process which of the following reducing agents is used:

In reaction $A + 2B {\rightleftharpoons} 2C + D$, initial concentration of $B$ was $1.5$ times of $[A]$, but at equilibrium the concentrations of $A$ and $B$ became equal. The equilibrium constant for the reaction is :

A gaseous hydrocarbon gives upon combustion $0.72\, g$ of water and $3.08\, g$ of $CO_2$. The empirical formula of the hydrocarbon is

The density of $3M$ solution of sodium chloride is $1.252\, g\, mL^{-1}$. The molality of the solution will be: (molar mass, $NaCl = 585\, g\, mol^{-1}$)

Which of the free radical is most stable?

Which one of the following statements about packing in solids is ?

For which of the following compounds Kjeldahl method can be used to determine the percentage of Nitrogen ?

A compound with molecular mass $180$ is acylated with $CH_3COCl$ to get a compound with molecular mass $390$. The number of amino groups present per molecule of the former compound is