All questions of Energy Resources for Grade 6 Exam

The process of conversion of dead plants material into coal is called carbonization.

Coal may be classified in rock types (or lithotypes) based on the presence of petrological components known as macerals. Based on maceral content and its appearance in a hand specimen, coal is classified into four principal types: clarain, durain, fusain, and vitrain.

Yes, coal tar is used to make synthetic dyes and if you might have seen (or smelt), coal tar is applied on roads and it smells ABSOLUTELY terrible

Paraffin wax is not obtained from coal tar; it is a constituent of petroleum. Coal tar produces substances like synthetic dyes, perfumes, and naphthalene balls.

Explanations:

Inexhaustible Natural Resources - Air
Air is considered an inexhaustible natural resource because it is constantly being replenished through natural processes such as photosynthesis and the water cycle. It is essential for the survival of all living organisms and plays a crucial role in maintaining the balance of ecosystems.

Exhaustible Natural Resources - Sunlight
Sunlight is considered an exhaustible natural resource because it is not available in unlimited quantities. While the sun provides an immense amount of energy, it is finite and will eventually burn out. Additionally, the amount of sunlight that reaches the Earth's surface can vary depending on factors such as location and time of day.

Inexhaustible Natural Resources - Water
Water is another example of an inexhaustible natural resource. Although the amount of freshwater on Earth is limited, water is constantly being recycled through the water cycle. This means that, unlike fossil fuels such as coal, water will not run out as long as the water cycle continues to function.
Overall, it is important to distinguish between inexhaustible and exhaustible natural resources in order to ensure sustainable use and conservation of our planet's resources.

Explanation:

Natural Resource - Air:
- Air is a natural resource that is essential for the survival of all living organisms on Earth.
- It is composed of gases such as oxygen, nitrogen, and carbon dioxide, which are crucial for various biological processes.
- Air is freely available in the environment and is not created by humans, making it a natural resource.

Man-made Resource - Soil:
- Soil is a natural resource that is formed over centuries through the weathering of rocks and organic matter decomposition.
- While soil itself is a natural resource, it can be managed and manipulated by humans through various agricultural practices.
- Therefore, soil is not considered a man-made resource but a natural resource that can be influenced by human activities.

Natural Resource - Plastic:
- Plastic is a man-made material produced from natural resources such as petroleum and natural gas.
- While the raw materials used to make plastic are natural resources, the final product itself is considered a man-made resource.
- Plastic does not occur naturally in the environment and is manufactured through human intervention.

Man-made Resource - Water:
- Water is a natural resource that is essential for all forms of life on Earth.
- While water itself is a natural resource, humans have developed technologies to treat and distribute water for various purposes.
- Therefore, water is a natural resource that can be managed and utilized by humans, but it is not considered a man-made resource.

Coal tar is a mixture of about 200 substances, used as starting materials for various industrial products.

The word petroleum is derived from the words "petra" (rock) and "oleum" (oil), thus commonly known as rock oil.

Understanding Coal Combustion
When coal is heated in the presence of air, it undergoes a chemical reaction known as combustion. This process primarily produces carbon dioxide as a result of burning carbon content found in coal.
What Happens During Combustion?
- Heat and Air Reaction: When coal is heated, it reacts with oxygen from the air.
- Carbon to Carbon Dioxide: The carbon in the coal combines with oxygen to form carbon dioxide (CO2).
- Energy Release: This reaction releases a significant amount of energy in the form of heat and light, making coal a valuable fuel source.
Why Carbon Dioxide is the Main Product?
- Chemical Composition: Coal is primarily composed of carbon, along with some hydrogen, sulfur, and other elements. The combustion process favors the formation of carbon dioxide due to the abundance of oxygen in the air.
- Environmental Impact: The release of carbon dioxide contributes to greenhouse gas emissions, which is a concern for climate change.
What About Other Options?
- Water Vapor: While water vapor can be produced during combustion (especially from hydrogen in coal), it is not the primary product.
- Oxygen and Nitrogen: Oxygen is consumed during combustion, and nitrogen, although present in the air, does not react significantly with coal at combustion temperatures.
In conclusion, when coal is heated in air, the main product formed is carbon dioxide, making option 'B' the correct answer. Understanding this process is crucial for recognizing the environmental implications of coal usage.

Understanding Natural Gas Storage
Natural gas is a vital energy source used for heating, electricity generation, and as fuel for vehicles. Its storage is crucial for managing supply and demand.
What is Compressed Natural Gas (CNG)?
- CNG stands for Compressed Natural Gas.
- It is natural gas that has been compressed to less than 1% of its volume at standard atmospheric pressure.
- CNG is stored in high-pressure containers, making it efficient for storage and transportation.
Why is CNG Used for Storage?
- Safety: CNG is non-toxic and produces fewer emissions compared to other fossil fuels.
- Efficiency: Compressing natural gas allows for easy transport and storage, especially in areas without pipeline access.
- Versatility: CNG can be used in various applications, including vehicles, industrial processes, and residential heating.
Comparison with Other Fuels
- Coal: A solid fossil fuel, coal is not stored under pressure and is used primarily for electricity generation.
- Diesel: A liquid fuel derived from crude oil, diesel is stored in tanks but does not involve compression like CNG.
- Petrol: Also a liquid fossil fuel, petrol is used mainly in internal combustion engines and is stored in liquid form.
Conclusion
Compressed Natural Gas (CNG) is the preferred method for storing natural gas under high pressure due to its safety, efficiency, and versatility. Understanding these differences helps in appreciating the role of CNG in our energy systems.

Coke is a tough, porous, and black substance that is almost a pure form of carbon. It is used in the manufacture of steel and in the extraction of many metals.

Understanding Jet Fuel: Kerosene
Jet aircraft require a specific type of fuel that can perform efficiently at high altitudes and speeds. The correct answer to the question is **kerosene**.

What is Kerosene?
- Kerosene is a liquid hydrocarbon fuel derived from petroleum.
- It is commonly used as a fuel in jet engines, particularly in commercial aviation.

Why Kerosene for Jet Aircraft?
- **High Energy Density**: Kerosene provides a high energy output, which is essential for powering jet engines.
- **Low Freezing Point**: Kerosene remains liquid at very low temperatures, which is critical for high-altitude flights where temperatures can drop significantly.
- **Stability**: It has good stability and can be stored for long periods without degradation.

Comparison with Other Fuels
- **Petrol**: Generally used in cars, it has a higher volatility and is not suitable for jet engines.
- **Diesel**: While it is used in some types of engines, it is heavier and not ideal for aviation applications.
- **Lubricating Oil**: This is used to reduce friction in engines but is not a fuel source.

Conclusion
In summary, kerosene is the preferred fuel for jet aircraft due to its efficiency, stability, and suitability for high-performance engines. Understanding the properties of different fuels helps in recognizing why certain fuels are used in specific applications, such as aviation.

CNG stands for Compressed Natural Gas, which is natural gas stored under high pressure.

Petroleum gas in liquid form (LPG) is primarily used as fuel for homes and industries.

Paraffin wax, obtained from petroleum, is primarily used for making candles, ointments, and vaseline.

CNG (Compressed Natural Gas) is less polluting and used in transport vehicles due to its cleaner combustion.

Coke, an almost pure form of carbon obtained from coal, is used in the manufacture of steel.

Answer:

Introduction:
The petroleum product used for surfacing roads is called bitumen. Bitumen is a thick, black, viscous liquid or semi-solid form of petroleum. It is primarily used in road construction and maintenance due to its excellent adhesive and waterproofing properties.

Explanation:
Bitumen is derived from the fractional distillation of crude oil. During the refining process, bitumen is obtained when the heaviest components of crude oil are separated from the lighter fractions. It is composed mainly of hydrocarbons, which are organic compounds composed of hydrogen and carbon atoms.

Properties of Bitumen:
Bitumen possesses several properties that make it suitable for surfacing roads:

1. Adhesion: Bitumen has excellent adhesive properties, allowing it to bind aggregates together. This property helps to create a strong and durable road surface.

2. Waterproofing: Bitumen is highly impermeable to water, preventing water from seeping into the road structure. This helps in protecting the underlying layers from water damage, such as weakening of the base and subbase layers due to moisture.

3. Flexibility: Bitumen exhibits high elasticity, which helps the road surface to withstand heavy traffic loads and temperature variations. It can expand and contract without cracking, ensuring the road's longevity.

4. Viscosity: Bitumen has a high viscosity, meaning it is thick and sticky at normal temperatures. This property allows it to coat and adhere to aggregates during the road construction process.

5. Resistance to Oxidation: Bitumen has good resistance to oxidation, which helps in maintaining its properties over extended periods. It can withstand exposure to sunlight, air, and other environmental factors without significant degradation.

Application:
Bitumen is commonly used in road construction and maintenance in the following ways:

1. Asphalt Concrete: Bitumen is mixed with aggregates such as crushed stone, sand, and gravel to create asphalt concrete, which forms the topmost layer of roads. This mixture provides a smooth and durable road surface that can withstand heavy traffic.

2. Surface Dressing: Bitumen is applied as a thin layer onto existing road surfaces to improve their durability and skid resistance. This process is known as surface dressing or chip sealing.

3. Bituminous Emulsion: Bitumen can be emulsified with water to form a bituminous emulsion. This emulsion is used for surface treatments like slurry seals and micro-surfacing, which help in preserving and extending the life of roads.

Conclusion:
Bitumen is a crucial petroleum product used for surfacing roads. Its adhesive, waterproofing, and flexible properties make it an ideal choice for road construction and maintenance. By using bitumen, we can ensure the durability, safety, and longevity of road surfaces, providing a smooth and reliable transportation network.

Gujarat has a network of pipelines for transporting natural gas, including cities like Vadodara.