St. Thomas’ Day School | Class 11 Unit 2 Examination | 6 Dec 2023

School	:	St. Thomas’s Day School
Class	:	11
Exam	:	Unit 2
Subject	:	Chemistry
Date	:	12 Dec 2023
Time	:	2 hour
Marks	:	50

St. Thomas’s Day School

Class 11 | Unit 2 Examination

Section A

A. Choose the correct option from the choice given: [10]

1. For the reaction N₂ + 3H₂ = 2NH₃, the value of Δn will be

1. -2
2. -1
3. 1
4. 6

2. The IUPAC name  of the compound C₂H₅OC₂H₅ is

1. methoxy ethane
2. ethoxy ethane
3. ethyl ethanoate
4. butanone

3. The hybridization and geometry of carbon atoms in alkene molecules is

1. sp³, tetrahedral
2. sp³, square planar
3. sp², trigonal planar
4. sp, linear

4. Which of the following compounds have maximum covalent character?

1. NaCl
2. NaI
3. NaBr
4. NaF

5. The oxidation state of the carbon atom in glucose molecules is

1. 2
2. -4
3. 6
4. 0

6. The catalyst required for the hydrogenation of vegetable oils into fats is

1. Platinum
2. iron
3. nickel
4. Ziegler Natta

7. The monomer of PVC is called

1. ethylene
2. vinyl chloride
3. styrene
4. tetrafluoroethylene

8. Baeyer’s reagent is alkaline KMnO₄. It gets decolourized when we add it to

1. propene
2. propane
3. propanol
4. propanal

9. Which of the following alkanes will have the highest melting point

1. methane
2. ethane
3. propane
4. butane

10. Chromium has unusual electronic configuration due to

1. Half filled d subshell
2. Fully filled d subshell
3. incompletely filled d subshell
4. None of the above reasons

B. Carry out the following conversions: [5]

1. ethene to ethane
2. ethyl chloride to ethene
3. ethanol to ethene
4. sodium acetate to methane
5. methane to methanol

C. Draw the structures of the following Compounds [5]

1. 2,2 – dimethyl propane
2. butan 1,4 – dioic acid
3. pent-2-ene-1-al
4. 3-hydroxy hexane-1-ol
5. pent-1-ene-4-yne

Section B

Question 1 TO 5 Carry 2 Marks Each

Question 1:

Write the electronic configuration of the following species:

(a) Mn²⁺

(b) P

Question 2:

Find the oxidation states of the underlined atoms

(a) KMnO₄

(b) Na₂S₄O₆

Question 3:

State the law of mass action and the law of chemical equilibrium.

Question 4:

What is isomerism in organic compounds? Explain with an example.

Question 5:

(a) Give reasons why para nitro phenol has higher boiling point thanortho nitro phenol.

OR

(b) H_₂⁺exists.Explain with molecular orbital theory.

Questions 6 to 10 carry 3 Marks Each

Question 6:

Draw the Lewis dot structures of the following compounds:

(a) nitric acid

(b) sulphur dioxide

(c) chloric acid

Question 7:

State any three properties that make carbon a unique element.

Question 8:

Derive the relationship between K_p and K_c.

Question 9:

A sample of HI gas is placed in the flask at a pressure of 0.2 atm. At equilibrium, the partial pressure of Hl gas is 0.04 atm. What is Kp for the given equilibrium?

2HI(g) ↔ H_₂(g) + I_₂(g)

Question 10:

(a) Using Le-Chatelier’s principle, predict the effect of

1. decreasing the temperature
2. Increasing the pressure
3. Removing the product

On the following equilibrium: N_₂ + O_₂ ↔ 2NO – heat.

OR

(b) Balance the following equation by oxidation number method:

H_₂S + HNO_₃ → NO + S + H_₂O

Question 11 Carry 5 Marks

Question 11

(a) Balance the following equations by ion electron method:

1. H₂O₂ + Fe₂⁺ → Fe³⁺ + H_₂O (acidic medium)
2. Cl_₂ + IO^3- + OH^– → Cl^– + IO^4- + H_₂O (basic medium)

OR

(b) i. Write two chemical reactions to justify that hydrogen peroxide can function as an oxidising as well as a reducing agent. [2|

ii. Draw the molecular orbital diagram for the nitrogen molecule. Calculate the bond order and predict its magnetic behaviour. [3]