Methane is prepared in the laboratory by heating a mixture of sodium acetate and______.

A. Water

B. Soda lime

C. Lime stone

D. Sodium carbonate

Methane can be prepared in the laboratory by heating a mixture of sodium acetate and soda lime. Therefore, the correct answer is B. Soda lime. Let’s delve into the reasoning behind this process and how it works.

Understanding the Reaction

The preparation of methane from sodium acetate involves a process known as decarboxylation. When sodium acetate (CH₃COONa) is heated with soda lime, which is a mixture of sodium hydroxide (NaOH) and calcium oxide (CaO), a chemical reaction occurs that leads to the formation of methane (CH₄).

The Chemical Equation

The overall reaction can be represented as follows:

• CH₃COONa + NaOH → CH₄ + Na₂CO₃ + H₂O

In this reaction, sodium acetate reacts with sodium hydroxide to produce methane, sodium carbonate, and water. The key here is the presence of soda lime, which provides the necessary sodium hydroxide for the reaction to take place.

Why Not the Other Options?

Let’s briefly examine why the other options do not work for preparing methane:

• Water: Simply adding water to sodium acetate does not facilitate the production of methane. Water is not a strong enough base to drive the decarboxylation process.
• Lime Stone: Lime stone (calcium carbonate) does not participate in the reaction to produce methane. It is primarily used in other chemical processes, such as the production of lime.
• Sodium Carbonate: While sodium carbonate is a product of the reaction, it cannot be used as a reactant in this context to produce methane.

Practical Applications

The laboratory preparation of methane is significant not only for educational purposes but also for understanding organic chemistry and gas reactions. Methane is a fundamental hydrocarbon and serves as a primary component of natural gas, making it essential in various industrial applications.

Summary of Key Points

To summarize, the preparation of methane in the laboratory involves heating sodium acetate with soda lime, leading to the production of methane gas. This reaction highlights the importance of understanding chemical interactions and the role of different compounds in organic synthesis.