List of top Chemistry Questions

From the following, identify the favorable conditions for physical adsorption:

• I) Large surface area
• II) Low temperatures
• III) High temperatures
• IV) High pressures

Which of the following represents the roasting of the ore?

Which of the following aqueous solutions has the highest osmotic pressure?

The allotrope of carbon which is used as an abrasive for sharpening hard tools is

The number of moles of OH\(^-\) ions present in 100 mL of 0.2 M Al(OH)\(_3\) solution is (assume 100% dissociation)

Identify the correctly matched pair from the following:

Which of the following is not correct for Frenkel defect?

500 mL of 0.1M HCl is mixed with 500 mL of 0.02M HA (weak acid) solution. To this solution, 2 g of solid NaOH is added. What is the pH of the resultant solution? (Given} \( K_a \) of HA is \( 4 \times 10^{-10} \), molar mass of NaOH is 40 g/mol, log 2 = 0.3, log 4 = 0.6\bf{)

If the standard molar enthalpies of formation of \( C_2H_5OH(l)) \), \( CO_2(g) \), and \( H_2O(l) \) are -278, -394, and -286 kJ mol\(^{-1}\) respectively, the standard enthalpy of combustion of the reaction \[ C_2H_5OH(l) + 3O_2(g) \rightarrow 2CO_2(g) + 3H_2O(l) \] in kJ mol\(^{-1}\) is:

Which one of the following options is correct for \[ q = -ve, \, w = +ve \{ (where \(q\) and \(w\) are heat and work respectively)} \]

The alloy formed by lithium with metal 'X' is used to make armour plates. 'X' is

Among the following, which is the correct statement?

The element with atomic number 118 will be:

Identify the correct statements from the following:
(I) According to Charles' law, at constant pressure, the volume of a gas is directly proportional to its temperature.
(II) The rate of diffusion of a certain mass of a gas is inversely proportional to its density, at constant pressure and temperature.
(III) The kinetic energy of a gas is directly proportional to T (K).

At 300 K, 1 g of an ideal gas (A) exerted a pressure of 2 atm in a closed container. When 2 g of another ideal gas (B) was introduced into this container at the same temperature, the pressure changed to 3 atm. The correct relationship between the molar mass of A (\(M_A\)) and B (\(M_B\)) is:

The total number of electrons in antibonding molecular orbitals of \( O_2 \) is:

The number of antibonding electrons in \( N_2^+ \), \( O_2^+ \), \( O_2^- \) is respectively:

The wave number of a photon is \( 10^4 \, cm^{-1} \). What is its energy in joules? Given: \[ h = 6.6 \times 10^{-34} \, Js, \quad c = 3 \times 10^{10} \, cm/s, \quad \tilde{\nu} = 10^4 \, cm^{-1} \]

Which of the following contains 10 electrons, 11 protons, and 12 neutrons?

For the following reaction:
N₂(g)+3H₂(g)⇌2NH₃ (g)
The free energy changes at 25°C and 35°C are-33.089 and-28.018 kJ respectively. The heat of the reaction is

Match List I with List II

LIST I		LIST II
A	Cobalt catalyst	I	\((H_2​+Cl_2​)\) production
B	Syngas	II	Water gas production
C	Nickel catalyst	III	Coal gasification
D	Brine solution	IV	Methanol production

Choose the correct answer from the options given below:

The number of units, which are used to express concentration of solutions from the following is _______
Mass percent, Mole, Mole fraction, Molarity, ppm, Molality