Alessandro Giuseppe Antonio Anastasio Volta was an Italian scientist who studied chemistry and physics. He made important contributions to the understanding of electricity and power. Volta is known for inventing the electric battery and discovering methane, a type of gas. In 1799, he created the voltaic pile, a device that produced electricity through chemical reactions. He shared his findings in a letter to the Royal Society in London, which was published in 1800. His work showed that electricity could be generated using chemicals, not only by living organisms. This discovery inspired other scientists and helped create the field of electrochemistry.

Napoleon Bonaparte admired Volta’s work and invited him to the Institute of France to demonstrate his invention. Volta was honored by the emperor throughout his life. He taught experimental physics at the University of Pavia for nearly 40 years and was respected by his students. Although he was successful in his career, Volta valued family life, especially in his later years. He lived more privately and focused on his family. Volta died in 1827 after suffering from several illnesses that began in 1823. The unit of electric potential, the volt, is named in his honor.

Early life and marriage

Alessandro Volta was born on February 18, 1745, in Como, a town located in northern Italy. His father, Filippo Volta, was from a noble family. His mother, Donna Maddalena, was from the Inzaghi family. In 1794, Volta married Teresa Peregrini, a noblewoman from Como. Together, they raised three sons: Zanino, Flaminio, and Luigi.

Career

In 1774, he became a professor of physics at the Royal School in Como. One year later, he improved and made the electrophorus more well-known. The electrophorus was a device that produced static electricity. Because he promoted it so much, people often say he invented it, even though a similar machine was described in 1762 by Johan Wilcke, a Swedish experimenter. In 1777, he traveled through Switzerland, where he became friends with H. B. de Saussure, a physicist and mountaineer.

Between 1776 and 1778, Volta studied the chemistry of gases. He discovered methane after reading a paper by Benjamin Franklin about "flammable air." In November 1776, he found methane in the marshes of Angera near Lake Maggiore, and by 1778, he successfully isolated it. He conducted experiments, such as igniting methane using an electric spark inside a closed container.

Volta also studied what is now called electrical capacitance. He developed separate methods to study electrical potential difference (V) and charge (Q), and he discovered that for a given object, these two are proportional. This discovery is known as Volta's Law of Capacitance. For this work, the unit of electrical potential was named the volt.

In 1779, he became a professor of experimental physics at the University of Pavia. He held this position for nearly 40 years. His lectures were so popular that Emperor Joseph II ordered the construction of a new "physical theatre," now called the "Aula Volta," based on a design by Leopold Pollack. The emperor also gave Volta money to buy scientific instruments, which he purchased in England and France. At the University History Museum of the University of Pavia, 150 of these instruments, used by Alessandro Volta, are still displayed.

Volta and Galvani

Luigi Galvani, an Italian physicist, found something he called "animal electricity" when two different metals were connected in a line with a frog's leg and to each other. Volta realized that the frog's leg acted as both a conductor of electricity (what we now call an electrolyte) and a way to detect electricity. He also understood that the frog's legs were not needed for the electric current, which came from the two different metals. Volta replaced the frog's leg with paper soaked in brine and used other methods he knew from his studies to detect the electricity. In this way, he discovered the electrochemical series and the rule that the electric force (emf) of a galvanic cell, made of two different metal electrodes separated by an electrolyte, is the difference between their electric properties (so, two identical metals and the same electrolyte create no electric force). This rule is known as Volta's Law of the electrochemical series.

In 1800, because of a disagreement about Galvani's ideas about electricity, Volta created the voltaic pile, an early battery that produced a steady electric current. Volta found that the best pair of different metals to make electricity was zinc and copper. At first, he tested single cells connected together, with each cell being a wine glass filled with brine where the two different metals were placed. The voltaic pile used cardboard soaked in brine instead of the glasses.

Early battery

When Volta announced his invention of the voltaic pile, he recognized the contributions of William Nicholson, Tiberius Cavallo, and Abraham Bennet.

The battery created by Volta is considered one of the first electrochemical cells. It has two electrodes: one made of zinc and the other made of copper. The electrolyte is either sulfuric acid mixed with water or a type of saltwater brine. The electrolyte contains hydrogen ions (H⁺) and sulfate ions (SO₄²⁻). Zinc, which is higher in the electrochemical series than copper and hydrogen, reacts by losing electrons and becoming zinc cations (Zn²⁺). These electrons travel to the copper electrode. Positively charged hydrogen ions (protons) gain electrons at the copper electrode, forming hydrogen gas (H₂) bubbles. This process makes the zinc rod the negative electrode and the copper rod the positive electrode. The battery has two terminals, and an electric current flows when they are connected. The chemical reactions in this voltaic cell are as follows:

Copper does not react but acts as a catalyst for hydrogen gas formation and as an electrode for the electric current. The sulfate ion (SO₄²⁻) does not react but moves toward the zinc anode to balance the charge of the zinc cations. However, this cell has some disadvantages. It is unsafe to handle because sulfuric acid, even when diluted, can be hazardous. Additionally, the battery’s power decreases over time because hydrogen gas accumulates on the copper electrode, forming a barrier between the copper and the electrolyte solution.

Last years and retirement

In 1809, Volta became an associated member of the Royal Institute of the Netherlands. In honor of his work, Volta was made a count by Napoleon Bonaparte in 1810.

Volta retired in 1819 to his estate in Camnago, a section of Como, Italy, now named "Camnago Volta" in his honor. He died there on March 5, 1827, shortly after his 82nd birthday. Volta’s remains were buried in Camnago Volta.

Volta’s legacy is honored by the Tempio Voltiano memorial, located in the public gardens near the lake. A museum built in his honor displays some of the equipment he used for experiments. Nearby is the Villa Olmo, which houses the Voltian Foundation, an organization that supports scientific activities. Volta conducted his experiments and created his first inventions near Como.

In the Old Campus of the University of Pavia, there is a classroom called Aula Volta. It was commissioned by Emperor Joseph II in 1787 for Alessandro Volta’s lectures. The University History Museum also contains many scientific instruments that belonged to Volta.

In 1927, an international physics conference called the Como Conference was held at Lake Como to celebrate the 100th anniversary of Volta’s death.

Volta’s image appeared on the Italian Lire 10,000 note from 1990 to 1997, along with a sketch of his voltaic pile.

In late 2017, Nvidia introduced a new GPU design called Volta, focused on workstations.

The electric eel species Electrophorus voltai, discovered in 2019 as the strongest natural producer of bioelectricity, was named after Volta.

Religious beliefs

Volta was raised as a Catholic and kept his beliefs throughout his life. He did not become a clergyman, as his family had hoped, which led some people to accuse him of not being religious. Others suggested he might not have believed in religion, pointing out that he did not join the Church or respond to the Church's calls. Despite these ideas, Volta expressed his faith in a statement where he shared his beliefs.

Publications

• De vi attractiva ignis electrici, ac phaenomenis inde pendentibus [The Attractive Force of an Electric Fire and Related Phenomena] (in Latin). Published in Novo Comi by Octavio Staurenghi in 1769. OCLC number: 1419897.

• Briefe über thierische elektricität (1900) [Letters about Animal Electricity]. Available through WorldCat.org libraries. Published in Leipzig by W. Engelmann.

• Untersuchungen über den Galvanismus, 1796–1800 [Studies on Galvanism]. Available through WorldCat.org libraries.

• Del modo di render sensibilissima la più debole elettricità sia naturale, sia artificiale [Of the Method to Make the Weakest Natural or Artificial Electricity Very Clear]. By Alexander Volta, Professor of Experimental Philosophy in Como, etc. Presented to the Royal Society on March 14, 1782. Available in WorldCat libraries.