Packing Fraction of SCC, BCC & FCC 🔥| Density Numericals | Solid State Lecture 5 Part -2 | VBU SEM-2

💎 *SOLID STATE CHEMISTRY – LECTURE 5 (PART 2)* Namaskar students! Welcome back to *Chemistry with Gautam* 🧪🎓 In this lecture, we will understand one of the most important topics in Solid State Chemistry: *Packing Fraction, Close Packing Arrangements (CCP & HCP), and Density Calculations for Cubic Crystals.* All concepts are explained step by step with diagrams, formulas, and important numerical relationships to help you prepare for university examinations and competitive entrance exams. 📚 *TOPICS COVERED IN THIS LECTURE* ✅ Packing Fraction of Simple Cubic (SC) Crystal ✅ Packing Fraction of Body-Centred Cubic (BCC) Crystal ✅ Packing Fraction of Face-Centred Cubic (FCC) Crystal ✅ Step-by-Step Calculation of Packing Efficiency ✅ Close-Packed Structures: CCP and HCP ✅ CCP Stacking Pattern: ABCABCABC… ✅ HCP Stacking Pattern: ABABABAB… ✅ Density of Cubic Crystals ✅ Density Formula and Its Derivation ✅ Density Calculations for SC, BCC and FCC Crystals ✅ Important Formulas for Numerical Problems 📐 *IMPORTANT FORMULAS* *Packing Fraction:* Packing fraction = Volume occupied by particles / Total volume of unit cell Approximate packing efficiencies: • Simple Cubic (SC): 52% • Body-Centred Cubic (BCC): 68% • Face-Centred Cubic (FCC/CCP): 74% *Density of a Unit Cell:* \[ \rho = \frac{nM}{N_Aa^3} \] Where: • \(\rho\) = Density of the crystal • \(n\) = Number of particles per unit cell • \(M\) = Molar mass • \(N_A\) = Avogadro constant • \(a\) = Edge length of the cubic unit cell 🎯 *WHO SHOULD WATCH THIS VIDEO?* This lecture is useful for: • B.Sc. Chemistry Semester 2 students • Vinoba Bhave University (VBU), Hazaribagh – affiliated colleges • Session 2025–29 students • Students preparing for CUET-PG, IIT-JAM, CSIR-NET, GATE and TIFR examinations 🎓 *LECTURE DETAILS* 📖 Subject: Solid State Chemistry 📌 Lecture: 5 (Part 2) 🏫 University: Vinoba Bhave University, Hazaribagh 📚 Semester: 2 📅 Session: 2025–29 👨‍🏫 Educator: Gautam Kumar 📺 Channel: Chemistry with Gautam 💡 *LEARN THE CONCEPT, UNDERSTAND THE FORMULA, AND SOLVE THE NUMERICAL!* 👍 LIKE this video if it helps you understand the concepts. 📲 SHARE it with your classmates. 🔔 SUBSCRIBE to Chemistry with Gautam for more Chemistry lectures and exam-oriented explanations. 💬 *COMMENT BELOW:* Which packing fraction is the most difficult to calculate — SC, BCC, or FCC? Thank you for learning with Chemistry with Gautam! #SolidStateChemistry #PackingFraction #PackingEfficiency #CCP #HCP #BCC #FCC #DensityOfUnitCell #VBUHazaribagh #BScChemistry #ChemistryWithGautam #IITJAM #CUETPG #CSIRNET