Question

The hydrogen-oxygen fuel cell has a standard emf of \(1.23 \mathrm{~V}\). What advantages and disadvantages are there to using this device as a source of power, compared to a 1.55-V alkaline battery?

Short answer

A hydrogen-oxygen fuel cell has the advantages of being environmentally friendly, more energy-efficient, and providing a continuous power supply. However, it has the disadvantages of being costly, having challenging hydrogen storage, and requiring substantial infrastructure development. On the other hand, a 1.55-V alkaline battery is affordable, readily available, and familiar to most users. However, it has a limited lifespan, lower efficiency, and poses environmental concerns due to the chemicals used in its construction.

Step-by-step solution

What is a hydrogen-oxygen fuel cell?

A hydrogen-oxygen fuel cell is a type of device that converts chemical energy into electrical energy. It produces electricity by reacting hydrogen and oxygen, with water being the only byproduct. The standard emf (electromotive force) for a hydrogen-oxygen fuel cell, which reflects its potential difference, is 1.23 V.

What is a 1.55-V alkaline battery?

A 1.55-V alkaline battery is a disposable electrochemical cell that generates electric current through a chemical reaction. It is a popular choice for many household electronic devices, such as toys and remote controls. As the name suggests, it has a potential difference of 1.55 V.

Advantages of hydrogen-oxygen fuel cell

Some advantages of using a hydrogen-oxygen fuel cell as a power source include: 1. Environmentally friendly: The byproduct of the hydrogen-oxygen fuel cell is water, making it a more environmentally friendly option compared to batteries that have harmful byproducts. 2. High efficiency: Fuel cells are generally more energy efficient than batteries, reducing energy waste. 3. Continuous power supply: Unlike disposable batteries, fuel cells can continuously produce electricity as long as there is a supply of hydrogen and oxygen. This makes it a more reliable power source for certain applications.

Disadvantages of hydrogen-oxygen fuel cell

Some disadvantages of using a hydrogen-oxygen fuel cell as a power source include: 1. Cost: Fuel cells are still relatively expensive compared to other power sources such as the 1.55-V alkaline battery. 2. Hydrogen storage: Storing hydrogen for use in fuel cells can be challenging, as hydrogen is an explosive gas and requires proper containment. 3. Infrastructure: The infrastructure for supplying hydrogen is not as widespread as the infrastructure for batteries.

Advantages of 1.55-V alkaline battery

Some advantages of using a 1.55-V alkaline battery as a power source include: 1. Affordability: Alkaline batteries are generally cheaper than hydrogen-oxygen fuel cells. 2. Availability: Alkaline batteries are readily available in stores and can be easily replaced. 3. Familiarity: Most people are familiar with the use and disposal of alkaline batteries, making them a popular choice for everyday devices.

Disadvantages of 1.55-V alkaline battery

Some disadvantages of using a 1.55-V alkaline battery as a power source include: 1. Environmental impact: Alkaline batteries contain harmful chemicals that can damage the environment. 2. Limited life: Unlike fuel cells, alkaline batteries have a limited lifespan and need to be replaced. 3. Lower efficiency: Batteries are generally less energy efficient than fuel cells, wasting more energy. By analyzing the pros and cons of each power source, students can better understand the potential advantages and disadvantages of using a hydrogen-oxygen fuel cell compared to a 1.55-V alkaline battery.

Key concepts

Electrochemical Cell

An electrochemical cell is a fascinating device that transforms chemical energy into electrical energy, allowing us to power our devices. These cells can be found in various forms, such as batteries and fuel cells. In a hydrogen-oxygen fuel cell, the chemical reaction involves hydrogen and oxygen combining to produce electricity, with water as the only byproduct. This contrasts with a traditional alkaline battery, where a chemical reaction within the cell generates the electric current, often resulting in byproducts that can be environmentally harmful.

The key characteristic of an electrochemical cell is its voltage or electromotive force (emf), which indicates the potential energy available to perform work. For instance, a hydrogen-oxygen fuel cell has a standard emf of 1.23 V, while a typical alkaline battery has an emf of 1.55 V. Though the alkaline battery provides higher voltage, the fuel cell offers more sustainable energy generation. Understanding these differences helps us choose the best option for powering our devices based on our needs and environmental considerations.

Environmental Impact

When comparing hydrogen-oxygen fuel cells and alkaline batteries, environmental impact is a critical consideration. Fuel cells have the distinct advantage of being more environmentally friendly since their only byproduct is water. This makes them a cleaner energy source, particularly in applications where reducing carbon footprints and pollution is essential.

On the flip side, alkaline batteries can pose environmental risks. They contain chemicals like potassium hydroxide and zinc, which can harm the environment when disposed of improperly. This often leads to pollution and can threaten wildlife and ecosystems. By choosing hydrogen-oxygen fuel cells over alkaline batteries, we can significantly reduce our environmental impact.

Energy Efficiency

Energy efficiency is an essential factor when assessing power sources. Fuel cells, such as hydrogen-oxygen fuel cells, tend to have higher energy efficiency compared to alkaline batteries. This means they can convert a greater proportion of their chemical energy into usable electrical energy with minimal waste.

Alkaline batteries, on the other hand, are generally less efficient. A significant portion of the energy stored in an alkaline battery can be lost as heat, leading to decreased performance and frequent replacements. The higher efficiency of fuel cells can make them more suitable for applications requiring a continuous and reliable power supply, reducing overall energy consumption.

Hydrogen Storage

While hydrogen-oxygen fuel cells offer impressive benefits, they do come with some challenges, particularly in hydrogen storage. Hydrogen is a highly combustible gas, requiring specialized storage solutions to ensure safety. Compressed hydrogen tanks, cryogenic storage, and chemical storage are some methods used to store hydrogen safely for fuel cell applications.

Developing and maintaining the necessary infrastructure for hydrogen storage and distribution can be costly and complex, presenting a barrier for widespread adoption of hydrogen-oxygen fuel cells. However, advancements in storage technology and infrastructure are gradually overcoming these challenges, making the transition to hydrogen-based power more feasible and attractive for broader applications.