List of top Chemistry Questions

Consider the following electrochemical cell at standard condition. $$ \text{Au(s) | QH}_2\text{ | QH}_X(0.01 M) \, \text{| Ag(1M) | Ag(s) } \, E_{\text{cell}} = +0.4V $$ The couple QH/Q represents quinhydrone electrode, the half cell reaction is given below: $$ \text{QH}_2 \rightarrow \text{Q} + 2e^- + 2H^+ \, E^\circ_{\text{QH}/\text{Q}} = +0.7V $$

Given below are two statements: Statement I: CH$_3$-O-CH$_2$-Cl will undergo $ S_N1 $ reaction though it is a primary halide.
Statement II: {CH_3-C(-CH_3)(-CH_3)-CH_2-Cl}
will not undergo $ S_N2 $ reaction very easily though it is a primary halide. In the light of the above statements, choose the most appropriate answer from the options given below:

Radius of the first excited state of Helium ion is given as:
$a_0$ = radius of first stationary state of hydrogen atom.

A transition metal (M) among Mn, Cr, Co and Fe has the highest standard electrode potential $ (M^{3+} / M^{2+}) $. It forms a metal complex of the type $ [M(CN)_6]^{4-} $. The number of electrons present in the $ e_g $ orbital of the complex is ________.

A molecule with the formula $ AX_4Y $ has all its elements from p-block. Element A is rarest, monoatomic, non-radioactive from its group and has the lowest ionization enthalpy value among A, X, and Y. Elements X and Y have first and second highest electronegativity values respectively among all the known elements.
The shape of the molecule is:

Which of the following acids is a vitamin?

Lanthanoid ions with $4f^7$ configuration are: (A) Eu$^{2+}$ (B) Gd$^{3+}$ (C) Eu$^{3+}$ (D) Tb$^{3+}$ (E) Sm$^{2+}$ Choose the correct answer from the options given below:

Which of the following electronegativity order is incorrect?

How many different stereoisomers are possible for the given molecule?

Given below are two statements:

Statement (I): In octahedral complexes, when $ \Delta_o < P $ high spin complexes are formed. When $ \Delta_o > P $ low spin complexes are formed.
Statement (II): In tetrahedral complexes because of $ \Delta_t < P $, low spin complexes are rarely formed.

In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements:
Statement I: The metallic radius of Al is less than that of Ga.
Statement II: The ionic radius of Al$^{3+}$ is less than that of Ga$^{3+}$.
In the light of the above statements, choose the most appropriate answer from the options given below:

The correct order of basic nature on aqueous solution for the bases $ \text{NH}_3 $, $ \text{NH}_2 $, $ \text{CH}_3 \text{NH}_2 $, $ \text{CH}_3 \text{CH}_2 \text{NH}_2 $, $ (\text{CH}_3 \text{CH}_2)_2 \text{NH} $ is:

Given below are two statements:
Statement I: Vanillin will react with NaOH and also with Tollen’s reagent.

Statement II: Vanillin will undergo self-aldol condensation very easily.

In the light of the above statements, choose the most appropriate answer from the options given below:

Among SO₃, NF₃, NH₃, XeF₂, CIF$_3$, and SF₆, the hybridization of the molecule with non-zero dipole moment and one or more lone-pairs of electrons on the central atom is:

A solution is made by mixing one mole of volatile liquid A with 3 moles of volatile liquid B. The vapor pressure of pure A is 200 mm Hg and that of the solution is 500 mm Hg. The vapor pressure of pure B and the least volatile component of the solution, respectively, are:

Two vessels A and B are connected via stopcock. Vessel A is filled with a gas at a certain pressure. The entire assembly is immersed in water and allowed to come to thermal equilibrium with water. After opening the stopcock the gas from vessel A expands into vessel B and no change in temperature is observed in the thermometer. Which of the following statement is true?