List of top Chemistry Questions

Both acetaldehyde and acetone (individually) undergo which of the following reactions?
A. Iodoform Reaction
B. Cannizzaro Reaction
C. Aldol Condensation
D. Tollen's Test
E. Clemmensen Reduction
Choose the correct answer from the options given below:

The formation enthalpies, $\Delta H_f^\circ$ for $\text{H}_2$ and $\text{O}_2$ are 220.0 and 250.0 kJ mol $^{-1}$ , respectively, at 298.15 K, and $\Delta H_f^\circ$ for $\text{H}_2\text{O}$ (g) is -242.0 kJ mol $^{-1}$ at the same temperature. The average bond enthalpy of the O-H bond in water at 298.15 K is:

Given below is the plot of the molar conductivity vs $\sqrt{c}$ concentration for KCl in aqueous solution. If, for the higher concentration of KCl solution, the resistance of the conductivity cell is 100 $\Omega$ , then the resistance of the same cell with the dilute solution is 'x' $\Omega$ . The value of $x$ is:

When Ethane-1,2-diamine is added progressively to an aqueous solution of Nickel (II) chloride, the sequence of colour change observed will be:

Match List - I with List - II:

Choose the correct answer from the options given below:

Given below are two statements:

Statement I: Experimentally determined oxygen-oxygen bond lengths in the

O_2

are found to be the same and the bond length is greater than that of a

O=O

(double bond) but less than that of a single

O-O

bond.

Statement II: The strong lone pair-lone pair repulsion between oxygen atoms is solely responsible for the fact that the bond length in ozone is smaller than that of a double bond

O=O

but more than that of a single bond

O-O

.

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

Identify correct statement/s:
(A) $-\text{OCH}_3$ and $-\text{NHCOCH}_3$ are activating groups.
(B) $-\text{CN}$ and $-\text{OH}$ are meta directing groups.
(C) $-\text{CN}$ and $-\text{SO}_3\text{H}$ are meta directing groups.
(D) Activating groups act as ortho- and para-directing groups.
(E) Halides are activating groups.
Choose the correct answer from the options given below:

In the given structure, number of $sp$ and $sp^2$ hybridized carbon atoms present respectively are:

Given below are two statements:

The molarity of a 70%(mass/mass) aqueous solution of a monobasic acid (X) is:

For hydrogen atom, the orbital/s with lowest energy is/are:

Find the compound $A$ from the following reaction sequences:

A \xrightarrow{\text{aqua regia}} B \xrightarrow{(1) \, \text{KNO}_3, \, \text{NH}_4\text{OH}} \text{yellow ppt}.

The elemental composition of a compound is 54.2%C, 9.2%H, and 36.6%O. If the molar mass of the compound is 132 g/mol, the molecular formula of the compound is:

Which of the following mixing of 1M base and 1M acid leads to the largest increase in temperature?

Given below are two statements:

Statement (I): The first ionization energy of Pb is greater than that of Sn.
Statement (II): The first ionization energy of Ge is greater than that of Si.

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

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:

Match List - I with List - II.

Match List - I with List - II.

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

Quantitative analysis of an organic compound (X) shows the following percentage composition. C: 14.5% Cl: 64.46% H: 1.8% Empirical formula mass of the compound (X) is:

Consider the following sequence of reactions:
i)

\text{Mg}, \text{dry ether}

ii)

\text{CO}_2, \text{H}_2\text{O}^+

iii)

\text{NH}_3, \Delta

11.25 mg of chlorobenzene will produce $x \times 10^{-1}$ mg of product B. Given molar mass of C, H, O, N, and Cl as 12, 1, 16, 14, and 35.5 g mol $^{-1}$ , respectively, the value of $x$ is:

For a given reaction $R \rightarrow P$ , $t_{1/2}$ is related to $[A_0]$ as given in the table. Given: $\log 2 = 0.30$ . Which of the following is true?

$[A]$ (mol/L)	$t_{1/2}$ (min)
0.100	200
0.025	100

Based on the data given below:

E^\circ_{\text{Cr}_2\text{O}_7^{2-}/\text{Cr}^{3+}} = 1.33 \, \text{V}, \quad E^\circ_{\text{Cl}_2/\text{Cl}^-} = 1.36 \, \text{V}, \quad E^\circ_{\text{MnO}_4^-/\text{Mn}^{2+}} = 1.51 \, \text{V}, \quad E^\circ_{\text{Cr}^{3+}/\text{Cr}} = -0.74 \, \text{V}.

The strongest reducing agent is:

The structure of the major product formed in the following reaction is:

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.)

List - I	List - II
(A) Adenine	(I)
(B) Cytosine	(II)
(C) Thymine	(III)
(D) Uracil	(IV)