Skip to main content

Thomson's Atomic Model

 


We have talked about Dalton's Atomic theory in our previous blog. According to his theory atom was invisible and indestructible. In our last blog, we talked about charged particles of matter, also known as fundamental particles. Discovery of these fundamental particles, electrons and protons, led to the failure of aspects of Dalton's atomic theory. After this failure, it was considered necessary to know that how the electrons and protons are arranged in atom. 

To explain this, many scientists proposed various atomic models. J.J. Thomson was the first to propose a model for the structure of an atom. In the March of 1904, Thomson published his model of the atom in "Philosophical Magazine" the leading British science journal of the day. He proposed that the model of an atom is similar to Christmas pudding. The electrons are in a sphere of positive charge like dry fruits in a spherical Christmas pudding. We can also think of an watermelon. While the electrons are studded in the positively charged sphere like the seeds in watermelon.

His basic proposal was:

  • An atom consists of a positively charged sphere and the electrons are embedded in it. 
  • The negative and positive charges are equal in magnitude. So, the atom as a whole is electrically neutral.
Although the Thomson's model explained that atoms are electrically neutral, but the results of experiments carried out by other scientists could not be explained by this model. We will talk about some of them in our upcoming blogs. Until then, try to figure out why this model of Thomson failed in the first place. We will answer this in out next blog.

Fore more details refer to Beyond Reaction: Fundamental Chemistry




Comments

Popular posts from this blog

Electric Motor - Brief History, Definition, Application and FAQs

Brief history of Electric Motor The history of the electric motor is a fascinating journey through centuries of innovation and technological advancements. Here is a detailed overview of its evolution: The concept of electromagnetism, the fundamental principle behind electric motors, was first discovered by Hans Christian Ørsted in 1820. His experiments demonstrated that an electric current could produce a magnetic field, laying the groundwork for the development of electric motors. Michael Faraday, a British scientist, made significant contributions to the understanding of electromagnetism. In 1821, he built the first electric motor by using a simple electromagnetic apparatus. Faraday's experiments paved the way for further research into electric motors. The late 19th century saw the commercialization of electric motors for various industrial applications. Inventors such as Thomas Davenport, who patented one of the earliest electric motors in 1837, and Nikola Tesla, who dev...

Non-Conventional Sources of Energy - Introduction, Brief History, Types, Applications and FAQs

Brief history of non-conventional sources of energy Our reliance on fossil fuels is a relatively recent phenomenon. Throughout history, humanity has explored various ways to harness energy from the environment, laying the groundwork for the non-conventional energy sources of today. Let's embark on a journey through time to explore the development of these sustainable alternatives. Early Renewable Efforts: Wind and Water Power the Way The use of non-conventional energy sources stretches back centuries. Windmills, the forerunners of modern wind turbines, emerged in Persia (modern-day Iran and surrounding regions) around 7th century AD. These wind-powered machines were used for grinding grain and pumping water, showcasing the early understanding of harnessing wind's kinetic energy. Water power also played a significant role in early societies. Water wheels, powered by flowing rivers or streams, were used for milling grains and powering various mechanical processes. The concept ...

Electric Circuits - A brief overview of history, definition and applications

  Brief history of Electric Circuits Early Concepts: Ancient Wonders: While the concept of electric circuits as we know them didn't emerge until more recent times, early civilizations like the ancient Greeks had inklings of electrical phenomena. They observed static electricity through materials like amber, a substance that, when rubbed, attracted lightweight objects. 18th Century Enlightenment: Franklin's Experiments: In the mid-18th century, Benjamin Franklin's famous kite experiment demonstrated the connection between lightning and electricity. This period laid the groundwork for understanding the nature of electric charge. 19th Century Innovations: Ohm's Law: In the 1820s, Georg Simon Ohm formulated Ohm's Law, a fundamental principle that defines the relationship between voltage, current, and resistance in a circuit. This was a pivotal moment in understanding the quantitative aspects of electricity. Telegraphy and Electrical Communication: Morse ...