Question

The Contact process is the industrial method for manufacturing sulfuric acid. Write three balanced equations for the Contact process, starting with burning sulfur powder in oxygen gas.

Short answer

The balanced equations for the Contact Process are: 1) \( S + O_2 \rightarrow SO_2 \), 2) \( 2 SO_2 + O_2 \rightarrow 2 SO_3 \), and 3) \( SO_3 + H_2O \rightarrow H_2SO_4 \).

Step-by-step solution

Burn Sulfur in Oxygen

The first step in the Contact Process involves burning sulfur in the presence of oxygen to form sulfur dioxide. The chemical equation for this reaction is: \[ S (s) + O_2 (g) ightarrow SO_2 (g) \] This reaction requires oxygen gas and solid sulfur as reactants to produce sulfur dioxide gas.

Convert Sulfur Dioxide to Sulfur Trioxide

The next step involves the oxidation of sulfur dioxide to sulfur trioxide. This process is catalyzed using vanadium(V) oxide (V2O5) under high temperatures. The chemical equation for this is: \[ 2 SO_2 (g) + O_2 (g) ightarrow 2 SO_3 (g) \] This reaction demonstrates how sulfur dioxide reacts with additional oxygen to form sulfur trioxide.

Absorb Sulfur Trioxide into Water

The final step involves the absorption of sulfur trioxide into water to produce sulfuric acid. However, directly reacting sulfur trioxide with water leads to a mist, so it is first dissolved in concentrated sulfuric acid (oleum) and then diluted: \[ SO_3 (g) + H_2O (l) ightarrow H_2SO_4 (aq) \] Through this step, sulfur trioxide is converted into aqueous sulfuric acid.

Key concepts

Sulfuric Acid Production

Sulfuric acid is a key component in various industries, making its production crucial. The production of sulfuric acid involves several steps carried out in a series of chemical reactions known as the Contact Process. This process ensures the efficient production of sulfuric acid, which is essential for applications such as fertilizers, chemicals, and cleaning agents.
To begin, sulfur is burned in the presence of oxygen to produce sulfur dioxide, a colorless gas. This step sets the stage for further chemical transformations. Next, this sulfur dioxide undergoes oxidation to form sulfur trioxide. Finally, to transform sulfur trioxide into sulfuric acid, it is absorbed into water. However, a direct combination with water can create a hazardous mist. To avoid this, sulfur trioxide is absorbed into oleum, a mixture of sulfuric acid and sulfur trioxide, before being diluted to form the aqueous sulfuric acid. This careful sequence of reactions highlights the sophistication of the Contact Process.

Industrial Chemistry

Industrial chemistry refers to the large-scale application of chemical processes to transform raw materials into valuable products. In the case of sulfuric acid production via the Contact Process, industrial chemistry involves carefully controlled reactions that take place in a stepwise fashion.
Efficiency and safety are paramount when producing sulfuric acid industrially. The use of catalysts like vanadium(V) oxide accelerates the oxidation of sulfur dioxide to sulfur trioxide. This not only increases the yield but also saves energy and time, making it a staple in industrial applications.
Sulfuric acid production highlights the interplay between theoretical chemistry and practical industrial applications, showcasing the importance of industrial chemistry in modern society. This intricate process underscores the role of chemistry in creating products that boost economic growth and improve lives.

Chemical Equations

Balanced chemical equations are fundamental to understanding chemical reactions. They provide a shorthand way of representing the reactants and products involved, as well as their stoichiometric relationships.
In the Contact Process, the first equation illustrates sulfur burning in oxygen to form sulfur dioxide:

• \[ S (s) + O_2 (g) \rightarrow SO_2 (g) \]

Next, sulfur dioxide is oxidized to produce sulfur trioxide, with the help of a catalyst:

• \[ 2 SO_2 (g) + O_2 (g) \rightarrow 2 SO_3 (g) \]

Finally, sulfur trioxide is absorbed into water to form sulfuric acid, carefully following methodical steps:

• \[ SO_3 (g) + H_2O (l) \rightarrow H_2SO_4 (aq) \]

These equations highlight the precise nature of chemical reactions and emphasize the importance of balancing them to adhere to the law of conservation of mass. A balanced equation not only reflects the correct proportions but also guides practical application in industry.

Sulfur Trioxide Formation

At the heart of sulfuric acid production lies the formation of sulfur trioxide. This step is crucial as sulfur trioxide acts as an intermediate in producing the final product, sulfuric acid.
Sulfur trioxide formation is achieved by oxidizing sulfur dioxide using oxygen, facilitated by a vanadium(V) oxide catalyst. The reaction occurs at high temperatures to ensure the conversion is efficient and thorough. The reaction can be expressed with the chemical equation:

• \[ 2 SO_2 (g) + O_2 (g) \rightarrow 2 SO_3 (g) \]

The use of catalysts is significant in industrial chemical processes because they decrease the energy requirement for the reaction, making it more economical. Additionally, the controlled environment ensures the safe conversion of sulfur dioxide to sulfur trioxide, contributing to the production of high-quality sulfuric acid essential for myriad industrial applications.