List of top Chemistry Questions

The following reaction takes place in a galvanic cell \[ 2Cr(s)+3Cd^{2+}(aq)\rightarrow2Cr^{3+}(aq)+3Cd(s) \] What is \(\Delta_rG^\circ\) of this cell? Given: \[ F=96500~Cmol^{-1} \] \[ E_{Cd^{2+}/Cd}^{\circ}=-0.4V \] \[ E_{Cr^{3+}/Cr}^{\circ}=-0.74V \]

A water sample is contaminated with compound X (molar mass \(=120g~mol^{-1}\)). Its molality is \(10^{-4}m\). What is its concentration in ppm?

Observe the reaction sequence

Compound A forms sodium derivative with \(NaNH_2\). Find B and D.

Match the extra element present in the organic compound with reagent used for its detection.

In winter, polar stratospheric clouds formed over Antarctica provide surface on which compound X responsible for depletion of ozone is formed. What is X?

Given below are two statements Statement-I: Silicones have high thermal stability and high dielectric strength Statement-II: In silica Si-O bond enthalpy is very high

Which of the following are Position isomers?

The correct order of metallic radius of Al, Ga, In, Tl is

Observe the reaction set and identify A and D.

Which of the following represents the water-gas shift reaction?

The $\Delta_f\text{H}^\ominus$ of $\text{BaCO}_3\text{(s)}$, BaO(s) and $\text{CO}_2\text{(g)}$ is respectively $-1216.3$, $-553.5$ and $-393.5\text{ kJ mol}^{-1}$. What is the value of $x$ (in $\text{kJ mol}^{-1}$) in the following reaction? \[ \text{BaCO}_3\text{(s)} \xrightarrow{\Delta} \text{BaO(s)}+\text{CO}_2\text{(g)}-x \]

Which of the following is not the correct statement about group 1 elements?

Which of the following statements are correct? I. Liquid sodium metal is used as coolant in fast breeder nuclear reactor II. LiCl is deliquescent III. LiF and CsI have low solubility in water

The $\Delta_f\text{H}^\ominus$ of $\text{BaCO}_3\text{(s)}$, BaO(s) and $\text{CO}_2\text{(g)}$ is respectively $-1216.3$, $-553.5$ and $-393.5\text{ kJ mol}^{-1}$. What is the value of $x$ (in $\text{kJ mol}^{-1}$) in the following reaction? \[ \text{BaCO}_3\text{(s)} \xrightarrow{\Delta} \text{BaO(s)}+\text{CO}_2\text{(g)}-x \]

The following equilibrium is established at 1100 K in a closed V L flask: \[ C(s)+CO_{2}(g)\rightleftharpoons2CO(g) \] The pressure of equilibrium mixture is 1 atm. Among the gaseous compounds, CO has 84% by mass. $K_c$ of this reaction is (approximately) ($R=0.082~L~atm~mol^{-1}K^{-1}$). Assume that CO and $CO_2$ are ideal gases.

$\text{KMnO}_4$ oxidizes $\text{M}^{2+}$ to $\text{M}^{4+}$ in acid medium. $500\text{ mL}$ of $0.02\text{M}$ $\text{M}^{2+}$ solution requires $500\text{ mL}$ of $x\text{ M}$ $\text{MnO}_4^-$ solution for complete oxidation. The value of $x$ is:

$\text{BF}_3$ reacts with $\text{NH}_3$ in 1:1 ratio and gives 'X'. The hybridization and geometry around B and N atoms in 'X' respectively are:

The element with atomic number 114 has outer shell electron configuration as that of element 'X'. What is X?

The difference in bond angles between $\text{SO}_2$ and $\text{H}_2\text{O}$ is:

Consider the following oxides: $\text{SO}_2$, $\text{P}_2\text{O}_5$, $\text{SO}_3$, $\text{Al}_2\text{O}_3$, $\text{K}_2\text{O}$, MgO. The most acidic and most basic oxides are respectively:

A gaseous mixture contains $\text{H}_2$ and $\text{O}_2$. The pressure of the mixture is $1\text{ bar}$. The weight percentage of $\text{O}_2$ is 80. The ratio of partial pressures of $\text{H}_2$ and $\text{O}_2$ is:

In H atom, electron is present in $n_x$ state. The angular momentum of this electron is $1.051 \times 10^{-34}\text{ Js}$. What is the energy (in J) required to excite this electron from $n_x$ state to $(n_x+1)$ state? ($h = 6.6 \times 10^{-34}\text{ Js}$; $\pi = 3.14$)

If the length of a linear antenna is increased by $60\%$ and the wavelength of the signal is decreased by $20\%$, then the percentage increase in the effective power radiated by the antenna is:

In hydrogen atom, electron is present in $n_x$ state. The energy of Lyman spectral line of hydrogen spectrum originated from $n_x$ state is $1.635 \times 10^{-18}\text{ J}$. What is the approximate energy (in J) required to excite this electron from $n_x$ state to $(n_x+1)$ state?

If A, B and C represent the power gain, base resistance and collector resistance respectively of a transistor connected in common emitter configuration, then the common emitter current amplification factor is: