Class 11 Chemistry Model Question Set B

The number of significant figures in 0.004050 is:

a. 2

b. 3

c. 4

d. 5

The volume occupied by 0.5 mole of an ideal gas at STP (273 K and 1 atm) is approximately:

a. 5.6 L
b. 11.2 L
c. 22.4 L
d. 44.8 L

Which of the following quantum numbers determines the orientation of an orbital?

a. Principal quantum number
b. Azimuthal quantum number
c. Magnetic quantum number
d. Spin quantum number

Which element has the highest first ionization energy?

a. Na
b. Mg
c. Al
d. Si

The bond angle in a water molecule is approximately:

a. 90°
b. 104.5°
c. 109.5°
d. 120°

In the reaction 2 𝐹 𝑒 𝐶 𝑙 2 + 𝐶 𝑙 2 → 2 𝐹 𝑒 𝐶 𝑙 3 2FeCl 2 +Cl 2 →2FeCl 3 , the oxidizing agent is:

a. FeCl₂

b. FeCl₃

c. Cl₂

d. Fe

Which gas shows the greatest deviation from ideal behaviour at low temperature and high pressure?

a. He

b. H₂

c. NH₃

d. Ne

For an exothermic reversible reaction, increasing temperature shifts equilibrium towards:

a. Products

b. Reactants

c. Both sides equally

d. No change

Which of the following is a strong oxidizing agent?

a. H₂S
b. SO₂
c. O₃
d. NH₃

The metal present at the active centre of vitamin B₁₂ is:

a. Iron
b. Cobalt
c. Zinc
d. Magnesium

Which of the following compounds gives a positive test with ammoniacal silver nitrate?

a. Ethane

b. Ethene

c. Ethyne

d. Benzene

A compound contains 40% carbon, 6.67% hydrogen and 53.33% oxygen by mass. Its molecular mass is 180.

(a) Define empirical formula. [1]
(b) Calculate the empirical formula of the compound. [2]
(c) Determine its molecular formula. [2]

(a) State Heisenberg's uncertainty principle. [1]
(b) Write the electronic configuration of chromium (Cr, atomic number 24). [2]
(c) Why does chromium show an exceptional electronic configuration? [2]

(a) Define electronegativity. [1]
(b) Explain the variation of atomic radius across a period and down a group. [2]
(c) Why is the first ionization energy of magnesium greater than that of aluminium? [2]

(a) Define oxidation in terms of electron transfer. [1]
(b) Identify the oxidizing and reducing agents in the following reaction: [2]

(c) Balance the following equation by the oxidation number method. [2]

A gas occupies 2.0 L at 27°C and 1 atm pressure. It is heated to 127°C and compressed until its pressure becomes 2 atm.

(a) State the combined gas law. [1]
(b) Calculate its final volume. [3]
(c) Why do real gases deviate from ideal behaviour? [1]

For the reaction:

Initially, 0.5 mole of is taken in a 2 L vessel. At equilibrium, 40% of it is dissociated.

(a) Define chemical equilibrium. [1]
(b) Write the expression for . [1]
(c) Calculate the equilibrium concentrations of and . [2]
(d) Calculate the value of . [1]

(a) State Avogadro's law. [1]
(b) Derive the relationship between molecular mass and vapour density. [2]
(c) Calculate the molecular mass of a gas whose vapour density is 22. [2]

(a) What is meant by allotropy? [1]
(b) Write two differences between diamond and graphite. [2]
(c) Why is aluminium extracted by electrolysis rather than by reduction with carbon? [2]

(a) Define functional group. [1]
(b) Write the IUPAC names of the following compounds. [2]

i.

ii.

(c) Write the equation for the dehydration of ethanol to ethene. Mention the required condition. [2]

Urea is a very much demanded chemical fertilizer in agricultural country like Nepal because of the lack of domestic production. One of the raw materials for urea production is ammonia which is obtained from Haber’s process.

i. Draw a flow sheet diagram for the manufacture of Ammonia by Haber’s-Bosch Process. [3]

ii. What is the major challenge in establishing chemical industries in the countries like Nepal? Mention how such challenge can be strategically overcome. [2]

(a) Define electrolysis. [1]
(b) Write the electrode reactions occurring during the electrolysis of aqueous copper sulphate using inert electrodes. [2]
(c) Calculate the mass of copper deposited when a current of 2 A is passed through a suitable copper salt solution for 48 minutes 15 seconds. [3]
(Given: Atomic mass of Cu = 63.5, )
(d) What happens at the anode during the electrolysis of aqueous copper sulphate using inert electrodes? [2]

(a) Name the industrial process used for the manufacture of nitric acid from ammonia. [1]
(b) Write the chemical equations involved in the major steps of this process. [3]
(c) Mention the optimum conditions and catalyst used in the first step. [2]
(d) Write two uses of nitric acid. [2]

(a) Name the main raw materials used in the manufacture of cement. [2]
(b) Describe the major steps involved in cement manufacture. [3]
(c) What is the function of gypsum in cement? [1]
(d) Write any two uses of cement. [2]

(a) Describe the laboratory preparation of ethene from ethanol with a balanced chemical equation. [2]
(b) Write chemical equations for the reactions of ethene with: [3]

i. Hydrogen
ii. Bromine
iii. Hydrogen bromide

(c) What is addition polymerization? Write the equation for the polymerization of ethene. [2]
(d) Why does ethene decolourize bromine water? [1]