Question

In laboratory burners, we use: (a) Coal gas (b) Oil gas (c) Gobar gas (d) Producer gas

Short answer

Coal gas was historically used in laboratory burners for its clean and consistent flame properties.

Step-by-step solution

Identifying Usage Context

To determine which type of gas is used in laboratory burners, we first need to understand the context of different gases. Each type of gas has specific applications based on its energy content and combustion properties.

Analyzing Properties of Each Gas

- **Coal gas**: Historically used for lighting and cooking before natural gas became widespread. - **Oil gas**: Produced from crude oil, used when a liquid fuel is preferable. - **Gobar gas**: Biogas from organic matter like cow dung, primarily used for domestic purposes in rural areas. - **Producer gas**: Made from carbonaceous materials and used in large-scale industrial processes.

Application in Laboratory Settings

In laboratories, the typical gas used must be clean-burning and produce a consistent flame. This makes one of the gases more suitable based on its properties of low soot production, consistency, and cleanliness.

Selecting the Most Suitable Gas

Considering the cleanliness and application, **Producer gas** is identified as used for large industrial processes due to its mixed composition and lower energy content. Hence, it is unlikely to be used in laboratories.

Conclusion Based on Analysis

Given that laboratory burners require a gas with properties conducive to producing a clean, controlled flame, **coal gas** is historically noted for such use, despite declining by modern standards due to cleaner alternatives.

Key concepts

Coal Gas

Coal gas is a type of gas that was historically produced as a byproduct during the manufacturing of coke from coal. It was once widely used for lighting and cooking purposes until the introduction of natural gas, which is cleaner and more efficient. Coal gas was produced in gas plants and mainly consisted of hydrogen, methane, carbon monoxide, and volatile hydrocarbons.

One noteworthy aspect of coal gas is its ability to produce a steady flame, which made it a popular choice in household and laboratory settings in the past. Despite its former popularity, coal gas usage has significantly declined due to concerns about the toxic carbon monoxide it contains and the availability of cleaner alternatives.

However, understanding coal gas is crucial because it helps illustrate the evolution of fuel technologies and the shifting priorities towards cleaner energy sources.

• Contains hydrogen, methane, and carbon monoxide.
• Was used for lighting and cooking before widespread natural gas adoption.
• Development of cleaner remedies has reduced its current relevance.

Gas Properties

The properties of gases used in different applications can vary significantly. Each gas has specific characteristics that make it suitable for particular uses, including energy content, combustion behavior, and safety.

When considering gas properties for laboratory use, factors like energy output, cleanliness of combustion, flame stability, and level of contaminants become paramount. This is because laboratories require a consistent and clean flame for precise and controlled experimentation.

Let's look at some properties essential for laboratory gases:

• Energy Content: High energy content provides the necessary heat and is efficient for burner use.
• Combustion Cleanliness: A gas that burns cleanly minimizes soot and ash, ensuring equipment doesn't get contaminated.
• Flame Stability: A steady flame is critical in experiments where consistency is crucial.
• Safety: It's imperative to use gases that are safe to handle and combust in confined spaces like laboratories.

This is why coal gas had become a go-to for labs historically, its combustion properties allowed it to produce a manageable and useful flame, though with modern advances, new alternatives are now preferred.

Laboratory Applications

In the realm of laboratory applications, selecting the right type of gas for burners is vital for ensuring successful experimental outcomes. Laboratories demand gases that support clean combustion to avoid contamination and ensure precise results.

Historically, coal gas was favored in laboratory settings due to its suitable combustion properties. Its ability to produce a consistent and adequately hot flame made it ideal for performing chemical reactions and heating substances. However, modern laboratories now prefer more reliable and safer alternatives, such as natural gas and propane, which provide similar benefits without the associated risks of coal gas.

• Laboratories need a clear, consistent flame for precise experiments.
• Clean combustion helps in reducing potential contamination risks.
• Current preferences have shifted to safer and cleaner alternatives like natural gas.

While coal gas may have had its time, the ongoing pursuit for efficiency and safety in laboratory settings continues to drive the adoption of better technologies.