Fill in the blanks:

Burning of wood and coal causes ………… of air.

A liquid fuel used in homes is …………………

Fuel must be heated to its ……………. Before it starts burning.

Fire produced by oil cannot be controlled by……………….

Let’s break down your question step by step, filling in the blanks with the appropriate terms related to combustion and fuels.

Understanding Combustion and Fuels

The burning of wood and coal causes pollution of air. This is because when these materials burn, they release various harmful substances, including carbon dioxide, particulate matter, and other pollutants that can degrade air quality.

A liquid fuel commonly used in homes is kerosene. Kerosene is often utilized for heating and cooking, especially in areas where natural gas is not readily available.

Fuel must be heated to its ignition temperature before it starts burning. This is the minimum temperature required for the fuel to ignite and sustain combustion.

Fire produced by oil cannot be controlled by water. When water is applied to an oil fire, it can spread the flames further instead of extinguishing them, as oil is less dense than water and will float on top, allowing the fire to continue burning.

Key Concepts Explained

• Air Pollution: The combustion of fossil fuels like wood and coal releases not only carbon dioxide but also other harmful pollutants such as sulfur dioxide and nitrogen oxides, contributing to air quality issues.
• Kerosene: This liquid fuel is derived from petroleum and is widely used in heating systems and lamps. It has a relatively high energy content and burns cleanly compared to other fuels.
• Ignition Temperature: Each fuel has a specific temperature at which it will ignite. For example, the ignition temperature of kerosene is around 220°C (428°F). Understanding this concept is crucial for safe handling and storage of fuels.
• Oil Fires: In firefighting, using water on oil fires is dangerous because it can cause the fire to spread. Instead, fire extinguishers designed for oil fires, such as foam or dry chemical extinguishers, are recommended.

By grasping these concepts, you can better understand the implications of fuel use and combustion in our daily lives. Each aspect plays a significant role in safety, environmental impact, and energy efficiency.