HOTS (Higher Order Thinking Skills) 1. Why do we not use coal gas as a cooking fuel? 2. Why does petroleum float on water? 3. Why do different types of coal have different compositions? 4. Can we prepare coal and petroleum in a laboratory? 5. Suggest some methods to reduce LPG consumption at home?
HOTS (Higher Order Thinking Skills) 1. Why do we not use coal gas as a cooking fuel? 2. Why does petroleum float on water? 3. Why do different types of coal have different compositions? 4. Can we prepare coal and petroleum in a laboratory? 5. Suggest some methods to reduce LPG consumption at home?
The Correct Answer and Explanation is:
Here are the correct answers to the HOTS (Higher Order Thinking Skills) questions along with a detailed 300-word explanation:
1. Why do we not use coal gas as a cooking fuel?
Answer: Coal gas is toxic, contains harmful impurities, and is not as safe or efficient as LPG.
2. Why does petroleum float on water?
Answer: Petroleum is less dense than water and is immiscible, so it floats on the water surface.
3. Why do different types of coal have different compositions?
Answer: The composition varies due to differences in the age, pressure, temperature, and biological conditions under which the coal formed.
4. Can we prepare coal and petroleum in a laboratory?
Answer: No, they cannot be prepared in a laboratory because their formation takes millions of years under natural geological processes.
5. Suggest some methods to reduce LPG consumption at home.
Answer: Use pressure cookers, cover pots while cooking, use energy-efficient stoves, cook in bulk, and ensure regular maintenance of burners.
Explanation:
Coal gas, though once used for lighting and heating, is no longer favored for cooking because it contains toxic components like carbon monoxide and hydrogen sulfide, which pose serious health and safety risks. Modern cooking fuels like LPG are cleaner, safer, and more efficient.
Petroleum floats on water because it is less dense and does not mix with water. This property is critical in oil spill disasters where petroleum spreads on water surfaces, making cleanup challenging.
Coal exists in various forms like peat, lignite, bituminous, and anthracite, each with different carbon content and energy values. These differences arise due to the specific environmental conditions under which they formed. For instance, higher temperatures and pressures over longer geological times transform coal into harder, more carbon-rich forms.
Coal and petroleum are fossil fuels formed over millions of years from the remains of plants and animals buried under earth’s surface. Due to the long time scales and specific pressure-temperature conditions required, it is not possible to artificially create them in laboratories. While synthetic fuels can be engineered, they differ significantly from natural coal and petroleum.
To conserve LPG at home, several strategies can be adopted. Cooking with lids on pots reduces cooking time and energy use. Using pressure cookers cooks food faster, consuming less fuel. Regular maintenance of burners ensures efficient flame. Avoiding unnecessary boiling and preparing meals in larger quantities (batch cooking) also helps minimize repeated usage. Additionally, adopting solar cookers or induction stoves for certain tasks can significantly cut down LPG dependence.
