FBISE 9 & 10 Composite Biology PBA | Video 8: Investigation of carbon dioxide in exhaled air.

🔬 FBISE 9 & 10 Composite Biology PBA Preparation — Video 8 Welcome to Biology Education! In this practical, we investigate whether exhaled air contains carbon dioxide. 🧪 Topics covered in this video: ✅ Aim and principle of the experiment ✅ Apparatus and materials required ✅ Procedure for testing exhaled air ✅ Using limewater to detect carbon dioxide ✅ Observations and expected results ✅ Scientific explanation and conclusion ✅ Important PBA practice questions 📘 Key concept: Exhaled air contains carbon dioxide produced during cellular respiration. When exhaled air is passed through limewater, the limewater turns milky due to the formation of calcium carbonate. Word equation: Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water 🎯 Exam tip: Remember the reagent, procedure, observation and conclusion. The positive result is the formation of milky limewater. 📚 This is Video 8 in the FBISE 9 & 10 Composite Biology PBA Preparation playlist. 🔔 Subscribe to Biology Education for more Biology practicals, MCQs and examination preparation. 👍 Like this video and share it with your classmates. ⚠️ Follow your teacher’s laboratory safety instructions. Never taste laboratory chemicals or inhale them directly. #FBISE #BiologyPBA #CarbonDioxide #ExhaledAir #BiologyPracticals