Chemistry Combustion & Flame Part 14 (Questions) Class 8 VIII

TL;DR

This video discusses the conditions necessary for combustion, different types of fuels, and how the use of CNG in automobiles has reduced pollution in cities.

Transcript

hello friends this video on combustion and flame part 14 is brought to you by exam for your calm no more fear from exam so with this we have reached towards the end of this lesson so let us quickly look at some of the questions question number one list conditions under which combustion can take place now as I have mentioned before also that there a... Read More

Key Insights

• 🥵 Combustion requires a combustible substance, oxygen, and heat.
• 🫢 Burning wood and coal releases poisonous gases and smoke, causing air pollution.
• 🫢 CNG is a cleaner fuel that produces fewer harmful gases and leaves less residue.
• 😘 LPG is a better fuel than wood due to lower air pollution and higher calorific value.
• ❤️‍🔥 Water is not used to control fires involving electrical equipment due to its conductivity.
• ❤️‍🔥 Carbon dioxide and LPG are commonly used to control fires.
• ❤️‍🔥 The ignition temperature of a substance determines how easily it catches fire.

Questions & Answers

Q: What are the three necessary conditions for combustion to occur?

The three conditions are a combustible substance, oxygen, and heat. Combustion is the reaction of a substance with oxygen, releasing heat.

Q: Why does burning wood and coal cause air pollution?

Burning wood and coal release poisonous gases and smoke, leading to air pollution.

Q: How does the use of CNG in automobiles reduce pollution in cities?

CNG is a cleaner fuel, leaving less residue and producing fewer harmful gases when burned compared to petrol or diesel. This makes it more environmentally friendly.

Q: How does LPG compare to wood as a fuel?

LPG is more environmentally friendly than wood because it produces less smoke and harmful gases like carbon monoxide. It also has a higher calorific value, meaning it produces more heat energy when burned.

Summary & Key Takeaways

• Combustion requires three conditions: a combustible substance, oxygen, and heat.

• Burning wood and coal cause air pollution due to the release of poisonous gases and smoke.

• CNG is a cleaner fuel compared to petrol or diesel, resulting in less residue and harmful gases when burned.