List of top Chemistry Questions

Given below are some nitrogen containing compounds:
Each of them is treated with HCl separately. 1.0 g of the most basic compound will consume ...... mg of HCl.
(Given Molar mass in g mol$^{-1}$: C = 12, H = 1, O = 16, Cl = 35.5.)

Choose the correct statements:
(A) Weight of a substance is the amount of matter present in it.
(B) Mass is the force exerted by gravity on an object.
(C) Volume is the amount of space occupied by a substance.
(D) Temperatures below 0°C are possible in Celsius scale, but in Kelvin scale negative temperature is not possible.
(E) Precision refers to the closeness of various measurements for the same quantity. Choose the correct answer from the options given below:

The correct option with order of melting points of the pairs (Mn, Fe), (Tc, Ru) and (Re, Os) is:

The reaction $ \text{A}_2 + \text{B}_2 \to 2\text{AB} $ follows the mechanism: \[ \text{A}_2 \xrightarrow{k_1} \text{A} + \text{A} \, (\text{fast}), \quad \text{A} + \text{B}_2 \xrightarrow{k_2} \text{AB} + \text{B} \, (\text{slow}), \quad \text{A} + \text{B} \to \text{AB} \, (\text{fast}). \] The overall order of the reaction is:

1.24 g of $AX_2$ (molar mass 124 g mol$^{-1}$) is dissolved in 1 kg of water to form a solution with boiling point of 100.105°C, while 2.54 g of AY_2 (molar mass 250 g mol$^{-1}$) in 2 kg of water constitutes a solution with a boiling point of 100.026°C. $Kb(H)_2$$\text(O)$ = 0.52 K kg mol$^{-1}$. Which of the following is correct?

Match List - I with List - II:

Choose the correct answer from the given below options

Match List - I with List - II:

List - I:
(A) Amylase
(B) Cellulose
(C) Glycogen
(D) Amylopectin

List - II:
(I) β-C1-C4 plant
(II) α-C1-C4 animal
(III) α-C1-C4 α-C1-C6 plant
(IV) α-C1-C4 plant

If $a_0$ is denoted as the Bohr radius of the hydrogen atom, then what is the de-Broglie wavelength $ \lambda $ of the electron present in the second orbit of the hydrogen atom?

At temperature T, compound AB2 dissociates as $ AB_2 \rightleftharpoons A + \frac{1}{2} B_2 $, having degree of dissociation $ x $ (small compared to unity). The correct expression for $ x $ in terms of $ K_p $ and $ p $ is:

Match List - I with List - II:

List - I:

(A) $[ \text{MnBr}_4]^{2-}$
(B) $[ \text{FeF}_6]^{3-}$
(C) $[ \text{Co(C}_2\text{O}_4)_3]^{3-}$
(D) $[ \text{Ni(CO)}_4]$

List - II:

(I) d²sp³ diamagnetic
(II) sp²d² paramagnetic
(III) sp³ diamagnetic
(IV) sp³ paramagnetic

The product (P) formed in the following reaction is:

Given below are two statements:
Statement (I): The radius of isoelectronic species increases in the order: \[ \text{Mg}^{2+} < \text{Na}^{+} < \text{F}^{-} < \text{O}^{2-} \] Statement (II): The magnitude of electron gain enthalpy of halogens decreases in the order: \[ \text{Cl} > \text{F} > \text{Br} > \text{I} \] In light of the above statements, choose the most appropriate answer from the options given below:

The molar conductivity of a weak electrolyte when plotted against the square root of its concentration, which of the following is expected to be observed?

Total number of nucleophiles from the following is: $\text{NH}_3, PhSH, (H_3C_2S)_2, H_2C = CH_2, OH−, H_3O+, (CH_3)_2CO, NCH_3$

In the following substitution reaction:

The correct increasing order of stability of the complexes based on $ \Delta $ value is:

Consider a complex reaction taking place in three steps with rate constants $k_1$, $k_2$, and $k_3$ respectively. The overall rate constant $k$ is given by the expression $ k = \sqrt{\frac{k_1 k_3}{k_2}} $. If the activation energies of the three steps are 60, 30, and 10 kJ mol$^{-1}$ respectively, then the overall energy of activation in kJ mol$^{-1}$ is ________________(Nearest integer).

The hydrocarbon (X) with molar mass 80 g mol$^{-1}$ and 90%carbon has ________________ degree of unsaturation.

The possible number of stereoisomers for 5-phenylpent-4-en-2-ol is:________________

The observed and normal molar masses of compound MX₂ are 65.6 and 164 respectively. The percent degree of ionisation of MX₂ is ________________% (Nearest integer).

In Carius method of estimation of halogen, 0.25 g of an organic compound gave 0.15 g of silver bromide (AgBr). The percentage of Bromine in the organic compound is ________________ × 10^-1% (Nearest integer).
(Given: Molar mass of Ag is 108 and Br is 80 g mol^-1)

Match List - I with List - II.

For the reaction, $$ H_2(g) + I_2(g) \rightleftharpoons 2HI(g) $$ Attainment of equilibrium is predicted correctly by:

The conditions and consequences that favour the $ t_{2g}^3 e_g^1 $ configuration in a metal complex are:

The successive 5 ionisation energies of an element are 800, 2427, 3658, 25024 and 32824 kJ/mol, respectively. By using the above values, predict the group in which the above element is present: