atomic theory posited that all matter is made up small indestructible units he called atoms.
theorised a mechanical universe with small, solid masses in motion.
proposed that elements consisted of atoms that were identical and had the same mass and that compounds were atoms from different elements combined together.
developed the two laws of electrochemistry.
built one of the first cathode-ray tubes.
created the periodic table
proposed the theory of electromagnetism and made the connection between light and electromagnetic waves.
theorised that electricity was comprised of negative particles he called electrons.
experiments with cathode-ray tubes led him to confirm the work of earlier scientists by definitively demonstrating that cathode-rays have a negative charge.
discovered canal rays, which have a positive charge equal to an electron.
discovered radiation by studying the effects of x-rays on photographic film
determined the charge to mass ratio of electrons.
discovered alpha, beta, and gamma rays in radiation
discovered radium and polonium and coined the term radioactivity after studying the decay process of uranium and thorium.
came up with the term "isotope" to explain the unintentional breakdown of radioactive elements.
proposed the idea of quantization to explain how a hot, glowing object emitted light.
proposed an atomic model called the Saturnian Model to describe the structure of an atom.
found that inert gases have a “stable electron configuration
invented a device that could detect alpha particles.
discovered that the number of protons in an element determines its atomic number.
used a mass spectrograph to identify 212 isotopes.
proposed an atomic structure theory that stated the outer orbit of an atom could hold more electrons than the inner orbit.
proposed that electrons have a wave/particle duality.
created the first nuclear reaction, producing alpha particles
proposed the existence of anti-particles.
discovered neutrons, particles whose mass was close to that of a proton.
discovered nuclear fission.
discovered eight transuranium elements.
created the first man-made nuclear reactor.