List of top Chemistry Questions

The mass % of urea solution is 6. The total weight of the solution is 1000 g. What is its concentration in mol L\(^{-1}\)? (Density of water = 1.0 g mL\(^{-1}\))
(Given: C = 12u, N = 14u, O = 16u, H = 1u)

1 gram of sodium hydroxide was treated with 25 ml. of 0.75 M HCI solution, the mass of sodium hydroxide left unreacted is equal to :

The mass of particle X is four times the mass of particle Y. The velocity of particle Y is four times the velocity of X. The ratio of de Broglie wavelengths of X and Y is: 

Assertion (A): When NaCl is added to water, elevation in boiling point is observed. Reason (R): Elevation in boiling point is a colligative property.
Spin only magnetic moment is same for which of the following ions?
A. T3+
B. Cr2+
C. Mn2+
D. Fe2+
E. Se3+
Choose the most appropriate answer from the options given below
Explain why ortho-nitrophenol is more steam volatile than para-nitrophenol.
In which of the following ionic pairs, the second ion is smaller in size than the first ion?
The vapour pressure of a solvent at 283 K is 100 mm Hg. Calculate the vapour pressure of a dilute solution containing 1 mole of a strong electrolyte AB in 50 moles of the solvent at 283 K (assuming complete dissociation of solute AB).
A 6% solution of glucose (molar mass = 180 g mol\(^{-1}\)) is isotonic with a 2.5% solution of an unknown organic substance. Calculate the molecular weight of the unknown organic substance.
Which of the following is the correct structure for the given IUPAC name?
3-Methylpent-2-enal
Consider the following statements regarding osmotic pressure:
(A) Molar mass of a protein can be determined using the osmotic pressure method.
(B) The osmotic pressure is proportional to the molarity.
(C) Reverse osmosis occurs when a pressure larger than osmotic pressure is applied to the concentrated solution side.
(D) Edema occurs due to retention of water in tissue cells as a result of osmosis.
Choose the correct statements with reference to osmotic pressure:
How many Faradays are required for the oxidation of one mole of \( \text{H}_2\text{O} \) to \( \text{O}_2 \)?

The final product in the following reaction Y is: 

Identify the incorrect statement.

For the reaction: $A_2(g) \rightleftharpoons B_2(g)$

The equilibrium constant $K_c$ is given as 99.0. In a 1 L closed flask, two moles of $B_2(g)$ is heated to $T(K)$. What is the concentration of $B_2(g)$ (in mol L$^{-1}$) at equilibrium?

Identify the products R and S in the reaction sequence given. 

The concentration of 1L of \( CaCO_3 \) solution is 1000 ppm. What is its concentration in mol \( L^{-1} \)?
(Ca = 40 u, O = 16 u, C = 12 u)
The vapour pressures of A and B at 25°C are 75 mm Hg and 25 mm Hg, respectively. If A and B are mixed such that the mole fraction of A in the mixture is 0.4, then calculate the mole fraction of B in the vapour phase.
The melting and boiling points of Zn, Cd, and Hg are low.
The compound that will undergo SN1 reaction with the fastest rate is
The molecular formula of a coordinate complex is CoH\(_{12}\)O\(_6\)Cl\(_3\). When one mole of this aqueous solution of complex is reacted with excess of aqueous AgNO\(_3\) solution, three moles of AgCl were formed. What is the correct formula of the complex?
For the reaction X + 2Y → P, the differential form equation of the rate law is:
Observe the following reactions:
I. \( \text{CaCO}_3(s) \rightarrow \text{CaO}(s) + \text{CO}_2(g) \)
II. \( \text{Cl}_2(g) \rightarrow 2 \text{Cl}(g) \)
III. \( \text{H}_2\text{O}(l) \rightarrow \text{H}_2O(s) \)
Identify the reactions in which entropy increases.
In the reaction, (CH3)3C − O − CH3 + HI → Products, CH3OH and (CH3)3CCl are the products and not CH3I and (CH3)3COH. It is because
Arrange the following acids in increasing order of their acidic strengths: HCOOH, FCH₂COOH, NO₂CH₂COOH, ClCH₂COOH