1. According to the Kössel-Lewis approach, what is the primary force that holds atoms together in a molecule?
A) Magnetic force
B) Electrostatic attraction
C) Gravitational pull
D) Nuclear binding force
Answer: B) Electrostatic attraction

2. What does the octet rule state about chemical bonding?
A) Atoms share electrons to form a pair.
B) Atoms lose or gain electrons to achieve eight electrons in their valence shell.
C) Atoms share or transfer electrons to have a total of eight valence shells.
D) Atoms form bonds to minimize their energy.
Answer: B) Atoms lose or gain electrons to achieve eight electrons in their valence shell.

3. Which type of bond is formed when electrons are shared equally between two atoms?
A) Polar covalent bond
B) Nonpolar covalent bond
C) Ionic bond
D) Metallic bond
Answer: B) Nonpolar covalent bond

4. What is the shape of the CH4 molecule according to the VSEPR theory?
A) Trigonal planar
B) Linear
C) Tetrahedral
D) Pyramidal
Answer: C) Tetrahedral

5. What is the primary reason for deviations in bond angles in molecules like NH3 and H2O?
A) Lone pair-lone pair repulsion
B) Lone pair-bond pair repulsion
C) Bond pair-bond pair repulsion
D) None of the above
Answer: B) Lone pair-bond pair repulsion

6. Which of the following elements typically exhibits an incomplete octet in its compounds?
A) Carbon
B) Boron
C) Nitrogen
D) Oxygen
Answer: B) Boron

7. In molecular orbital theory, what is the bond order of the N2 molecule?
A) 1
B) 2
C) 3
D) 4
Answer: C) 3

8. How is the dipole moment mathematically defined?
A) µ = charge (Q) × distance (r)
B) µ = Q / r
C) µ = Q × 2πr
D) µ = Q² / r
Answer: A) µ = charge (Q) × distance (r)

9. What is the type of bond formed by the sideways overlap of p-orbitals?
A) Sigma bond
B) Pi bond
C) Ionic bond
D) Hydrogen bond
Answer: B) Pi bond

10. In resonance structures, what do formal charges help determine?
A) The total number of electrons in a molecule
B) The stability of the molecule
C) The molecular geometry
D) The number of bonds in a molecule
Answer: B) The stability of the molecule

11. Which type of bond is formed when there is a transfer of electrons between two atoms?
A) Ionic bond
B) Covalent bond
C) Metallic bond
D) Hydrogen bond
Answer: A) Ionic bond

12. The formation of NaCl involves which of the following processes?
A) Sharing of electrons
B) Transfer of electrons from Na to Cl
C) Sharing of protons between Na and Cl
D) Formation of hydrogen bonds
Answer: B) Transfer of electrons from Na to Cl

13. In which molecule does the octet rule fail due to an odd number of electrons?
A) H2O
B) NH3
C) NO
D) CH4
Answer: C) NO

14. What is the primary concept behind VSEPR theory?
A) Atoms repel one another equally in molecules.
B) Electron pairs in the valence shell repel one another to minimize repulsion.
C) Protons in the nucleus dictate molecular geometry.
D) Bonds form solely to stabilize energy levels.
Answer: B) Electron pairs in the valence shell repel one another to minimize repulsion.

15. Which of the following is an example of a molecule with a linear shape?
A) CH4
B) CO2
C) NH3
D) H2O
Answer: B) CO2

16. What type of hybridization is present in methane (CH4)?
A) sp
B) sp2
C) sp3
D) sp3d
Answer: C) sp3

17. In which compound is the central atom surrounded by more than eight electrons (expanded octet)?
A) NH3
B) H2O
C) SF6
D) CH4
Answer: C) SF6

18. What is the bond angle in a perfect tetrahedral molecule?
A) 90°
B) 104.5°
C) 109.5°
D) 120°
Answer: C) 109.5°

19. What is the shape of a molecule with the molecular formula AB2E2?
A) Linear
B) Trigonal planar
C) Bent
D) Tetrahedral
Answer: C) Bent

20. What kind of bond is formed by the head-on overlap of orbitals?
A) Sigma bond
B) Pi bond
C) Ionic bond
D) Metallic bond
Answer: A) Sigma bond

21. Which theory explains the geometry of a molecule by considering the repulsion between electron pairs?
A) Valence Bond Theory
B) Molecular Orbital Theory
C) VSEPR Theory
D) Octet Theory
Answer: C) VSEPR Theory

22. What is the formal charge of oxygen in the ozone molecule (O3)?
A) 0
B) -1
C) +1
D) Depends on the structure
Answer: D) Depends on the structure

23. How many valence electrons are there in the CO3²⁻ ion?
A) 20
B) 24
C) 28
D) 30
Answer: B) 24

24. What kind of bond is formed in a diatomic nitrogen molecule (N2)?
A) Single bond
B) Double bond
C) Triple bond
D) Ionic bond
Answer: C) Triple bond

25. Which of the following is true about resonance structures?
A) They are separate molecules that interconvert rapidly.
B) The real structure is a hybrid of all canonical forms.
C) They only apply to ionic compounds.
D) Resonance structures have real physical existence.
Answer: B) The real structure is a hybrid of all canonical forms.

26. Which molecule has zero dipole moment?
A) H2O
B) NH3
C) CH4
D) CHCl3
Answer: C) CH4

27. The dipole moment of water (H2O) is due to which of the following?
A) Linear molecular geometry
B) Bent molecular geometry
C) Presence of double bonds
D) Presence of triple bonds
Answer: B) Bent molecular geometry

28. Which statement is true about bond length?
A) It decreases as bond order increases.
B) It increases as bond order increases.
C) It is always the same for single, double, and triple bonds.
D) It is independent of bond strength.
Answer: A) It decreases as bond order increases.

29. Which molecule exhibits sp2 hybridization?
A) BF3
B) NH3
C) H2O
D) C2H6
Answer: A) BF3

30. Which of the following has the shortest bond length?
A) C-C
B) C=C
C) C≡C
D) C-H
Answer: C) C≡C

31. What is the bond order of O2 in its ground state?
A) 1
B) 2
C) 3
D) 4
Answer: B) 2

32. Which of the following does NOT obey the octet rule?
A) CH4
B) H2O
C) BeH2
D) NH3
Answer: C) BeH2

33. What is the geometry of SF6?
A) Tetrahedral
B) Trigonal planar
C) Octahedral
D) Square planar
Answer: C) Octahedral

34. What is the hybridization of the central atom in PCl5?
A) sp3
B) sp2
C) sp3d
D) sp3d2
Answer: C) sp3d

35. Which of the following bonds is the strongest?
A) Single bond
B) Double bond
C) Triple bond
D) Hydrogen bond
Answer: C) Triple bond

36. What is the molecular shape of NH3?
A) Linear
B) Trigonal planar
C) Trigonal pyramidal
D) Tetrahedral
Answer: C) Trigonal pyramidal

37. What is the geometry of the carbonate ion (CO3²⁻)?
A) Linear
B) Trigonal planar
C) Tetrahedral
D) Bent
Answer: B) Trigonal planar

38. Which of the following has the largest bond angle?
A) NH3
B) H2O
C) CH4
D) CO2
Answer: D) CO2

39. What is the reason for the lower dipole moment in NF3 compared to NH3?
A) Lone pair orientation
B) Higher electronegativity of fluorine
C) Absence of hydrogen bonds
D) Non-linear structure of NF3
Answer: A) Lone pair orientation

40. Which type of orbital overlap leads to the formation of a pi bond?
A) Axial overlap
B) Sidewise overlap
C) Spherical overlap
D) Radial overlap
Answer: B) Sidewise overlap

১. রাসায়নিক বন্ধন ও অণুর গঠন

রাসায়নিক বন্ধন সংজ্ঞা ও গুরুত্ব: বিভিন্ন পরমাণুর মধ্যে আকর্ষণ শক্তি রাসায়নিক বন্ধন নামে পরিচিত। রাসায়নিক বন্ধনের মাধ্যমে স্থিতিশীল অণু তৈরি হয়।
কোসেল-লুইস পদ্ধতি: ১৯১৬ সালে রাসায়নিক বন্ধনের ইলেকট্রনিক তত্ত্বটি ব্যাখ্যা করে। এটি অক্টেট নিয়ম প্রতিষ্ঠা করে, যেখানে একটি পরমাণুর বহিঃস্তরে ৮টি ইলেকট্রন থাকলে সেটি স্থিতিশীল হয়।
অক্টেট নিয়ম: ইলেকট্রন স্থানান্তর বা ভাগাভাগির মাধ্যমে অক্টেট গঠন।
কোভ্যালেন্ট বন্ধন: ইলেকট্রনের শেয়ারিং এর মাধ্যমে গঠিত বন্ধন।

২. রাসায়নিক বন্ধনের ধরণ

আয়নিক বন্ধন: ইলেকট্রনের সম্পূর্ণ স্থানান্তরের মাধ্যমে ধনাত্মক ও ঋণাত্মক আয়নের মধ্যে তৈরি বন্ধন।
কোভ্যালেন্ট বন্ধন: ইলেকট্রনের শেয়ারিং এর মাধ্যমে তৈরি। এটি সিগমা (σ) এবং পাই (π) বন্ধন হতে পারে।

৩. অণুর আকৃতি ও বন্ধনের বৈশিষ্ট্য

VSEPR তত্ত্ব: পরমাণুর ভ্যালেন্স শেলে ইলেকট্রন জোড়ের মধ্যে পারস্পরিক বিকর্ষণ অণুর আকৃতি নির্ধারণ করে।
বন্ধনের দৈর্ঘ্য ও কোণ: বন্ধন দৈর্ঘ্য হলো দুটি বন্ধনযুক্ত পরমাণুর কেন্দ্রের মধ্যে দূরত্ব। বন্ধন কোণ ইলেকট্রন জোড়ের বিন্যাস নির্ধারণ করে।
ডিপোল মোমেন্ট: বন্ধনের মেরুকরণ পরিমাপ করার উপায়।

৪. ভ্যালেন্স বন্ড তত্ত্ব

অরবিটাল ওভারল্যাপ ধারণা: পরমাণুর ভ্যালেন্স অরবিটালগুলি একে অপরের সাথে ওভারল্যাপ করে বন্ধন গঠন করে।
অরবিটালের সংমিশ্রণ: হাইব্রিডাইজেশনের মাধ্যমে নতুন অরবিটাল তৈরি হয় যা বন্ধনের আকৃতি এবং দিকনির্দেশনা নির্ধারণ করে।

৫. অণুর অস্বাভাবিক গঠন ও সীমাবদ্ধতা

অক্টেট নিয়মের ব্যতিক্রম: অসম্পূর্ণ অক্টেট, বর্ধিত অক্টেট এবং বিজোড় ইলেকট্রন বিশিষ্ট অণু।
রেজোনেন্স: একাধিক লুইস স্ট্রাকচার ব্যবহার করে অণুর প্রকৃত গঠন নির্ধারণ।

MCQs for NEET, JEE, IIT, NIT, CUET, CTET, and SSC Entrance Exams: Your Ultimate Preparation Guide

Are you preparing for competitive exams like NEET, JEE, IIT, NIT, CUET, CTET, or SSC? Multiple Choice Questions (MCQs) are a proven way to enhance your preparation strategy. These MCQs are designed to strengthen your concepts, boost problem-solving skills, and improve time management—key elements to ace any entrance exam.

Why MCQs Are Essential for Competitive Exams?

Concept Clarity: MCQs cover important topics, ensuring a deep understanding of fundamental concepts.
Time Management: Practicing MCQs improves speed and accuracy, essential for high-stakes exams.
Exam Pattern Familiarity: MCQs simulate the real exam pattern, helping you feel confident on the big day.

Benefits of Using These MCQs for NEET, JEE, IIT, and More

Targeted Preparation: Specially curated MCQs focus on the specific syllabus of exams like NEET, JEE, and CUET, making your study focused and efficient.
Wide Subject Coverage: Includes questions from Physics, Chemistry, Mathematics, Biology, and more.
Boosts Competitive Edge: High-quality MCQs ensure you're ready to tackle even the trickiest questions.

Exams These MCQs Help With:

NEET: For aspiring medical students.
JEE & IIT: For engineering and technical aspirants.
NIT Admissions: A stepping stone to prestigious National Institutes of Technology.
CUET: Common University Entrance Test for undergraduate programs.
CTET: A mandatory test for teachers.
SSC: Government job aspirants preparing for SSC exams.

Pro Tips to Use MCQs Effectively:

Regular Practice: Dedicate time daily to solve topic-wise MCQs.
Review and Revise: Go through solutions and explanations to understand your mistakes.
Mock Tests: Attempt full-length MCQ tests to build exam stamina.

Get Started Now!

Our extensive MCQ collections are tailored to help you succeed in NEET, JEE, IIT, NIT, CUET, CTET, and SSC. Start practicing today and take a step closer to your dream career. Bookmark this page and share it with fellow aspirants.

Tags:

MCQs for NEET, JEE MCQs, IIT preparation, CUET questions, CTET practice, SSC MCQs, competitive exam tips, entrance exam success.

Make your preparation smarter, not harder. Let these MCQs guide your way to success!

Questions & Answers HS (11th & 12th)

Thursday, November 21, 2024

MCQ Chemistry Unit 4: Chemical Bonding and Molecular Structure, HS 1st Year