List of top Chemistry Questions

Identify the correct statement(s):

Which of the following ion/ions is/are diamagnetic?

Which of the following statements is true about the equilibrium constant and rate constant of a single-step chemical reaction?

What will be the change in acidity if:
(i) CuSO₄ is added to saturated (NH₄)₂SO₄ solution,
(ii) SbF₅ is added to anhydrous HF?

The equivalent weight of \(\text{Na}_2\text{S}_2\text{O}_3\) (Gram molecular weight = \(M\)) in the given reaction is:
\[\text{I}_2 + 2 \text{Na}_2\text{S}_2\text{O}_3 \rightarrow 2 \text{NaI} + \text{Na}_2\text{S}_4\text{O}_6\]

The major product of the following reaction is:

Correct solubility order of AgF, AgCl, AgBr, AgI in water is:

The degree of dissociation of acetic acid is:

Which hydrogen-like species will have the same radius as the 1st Bohr orbit of a hydrogen atom?

Equal volumes of aqueous solution of 0.1 M HCl and 0.2 M H₂SO₄ are mixed. The concentration of H+ ions in the resulting solution is:

The compounds A and B are respectively:

From the compounds given below, the number of compounds which give a positive Fehling’s test is____.
Compounds: Benzaldehyde, Acetaldehyde, Acetone, Acetophenone, Methanal, 4-nitrobenzaldehyde, cyclohexane carbaldehyde.

Identify A and B in the given chemical reaction sequence : -

The ionization energy of sodium in \(kJ \;mol^{−1}\). If electromagnetic radiation of wavelength 242 nm is just sufficient to ionize sodium atom is ______.

What happens when D-glucose is treated with the following reagents? 
(a) Br$_2$ water 
(b) HCN

The option(s) with correct sequence of reagents for the conversion of P to Q is(are)

In a metal deficient oxide sample, M_XY₂O₄(M and Y are metals), M is present in both +2 and +3 oxidation states and Y is in +3 oxidation state. If the fraction of M²⁺ ions present in M is \(\frac{1}{3}\), the value of X is______.

To form a complete monolayer of acetic acid on 1g of charcoal, 100 mL of 0.5M acetic acid was used. Some of the acetic acid remained unadsorbed. To neutralize the unadsorbed acetic acid, 40 mL of 1M NaOH solution was required. If each molecule of acetic acid occupies P x 10⁻²³ m² surface area on charcoal, the value of P is _____.
[Use given data: Surface area of charcoal = 1.5 x 10² m²g⁻¹ ; Avogadro’s number (N_A) = 6.0 x 10²³ mol⁻¹ ]

The species formed on fluorination of phosphorus pentachloride in a polar organic solvent are

A sample initially contains only U-238 isotope of uranium. With time, some of the U-238 radioactively decays into Pb-206 while the rest of it remains undisintegrated.
When the age of the sample is P x10⁸ years, the ratio of mass of Pb-206 to that of U-238 in the sample is found to be 7. The value of P is _____.
[Given: Half-life of U-238 is 4.5 x10⁹ years; log_e2 = 0.693]

Among [Co(CN)₄]⁴⁻, [Co(CO)₃(NO)], XeF₄, [PCl₄ ]⁺, [PdCl₄ ]²⁻ , [ICl₄ ]⁻ , [Cu(CN)₄]³⁻ and P₄ the total number of species with tetrahedral geometry is _____.

An organic compound P having molecular formula C₆H₆O₃ gives ferric chloride test and does not have intramolecular hydrogen bond. The compound P reacts with 3 equivalents of NH₂OH to produce oxime Q. Treatment of P with excess methyl iodide in the presence of KOH produces compound R as the major product. Reaction of R with excess iso-butylmagnesium bromide followed by treatment with H₃O⁺ gives compound S as the major product.
The total number of methyl (−CH₃) group(s) in compound S is ____.

The compound(s) having peroxide linkage is(are)

For a double strand DNA, one strand is given below:

The amount of energy required to split the double strand DNA into two single strands is _____ kcal mol⁻¹.
[Given: Average energy per H-bond for A-T base pair = 1.0 kcal mol⁻¹, G-C base pair = 1.5 kcal mol⁻¹, and A-U base pair = 1.25 kcal mol⁻¹. Ignore electrostatic repulsion between the phosphate groups.]